¹ United Nations Convention on the Law of the Sea, opened for signature Dec. 10,1982,1833 UNTS 397, reprinted in United Nations, Official Text of the United Nations Convention on the Law of the Sea with Annexes and Index, UN Sales No. E.83.V.5 (1983) (entered into force Nov. 16,1994) [hereinafter LOS Convention].

² There are currently 132 states parties (visited Sept. 10,1999) <http://www.un.org/Depts/los/index.htm>.

³ Those located between the exclusive economic zones (EEZs) of adjacent or opposite coastal states, and beyond the coastal states’ EEZs in the high seas.

⁴ LOS Convention, supra note 1, Arts. 63, 64. See David Freestone & Zen Makuch, The Netu International Environmental Law of Fisheries: The 1995 UN Straddling Stocks Convention, 1996 Y.B. Int’l Envtl. L. 3; Peter G. G. Davies & Catherine Redgwell, The International Legal Regulation of Straddling Fish Stocks, 1996 Brit. Y.B. Int’l L. 199.

⁵ Agreement for the Implementation of the Provisions of the United Nations Convention on the Law of the Sea of 10 December 1982, Relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks, opened for signature Dec. 4, 1995, 34 ILM 1542 (1995) (not yet in force). Entry into force requires 30 ratifications or accessions. Currendy, there are 24 states parties, and 59 signatories (visited Aug. 6, 1999) <http://www.un.org/Depts/los/index.htm>.

⁶ To mention but two: First, the dispute between various fishing states (Poland, Japan, South Korea and China) and Russia over the unilateral extension of Russian fisheries jurisdiction incorporating the soolled peanut hole area of high seas in the Sea of Okhotsk surrounded by the Russian 200-nautical-mile EEZ. See Alex G. Oude Elferink, The Sea of Okhotsk Peanut Hole: De Facto Extension of Coastal State Control (POLOS Report No. 2/1997, Fridtjof Nansen Institute, 1998). Second, the Fislieries Jurisdiction case between Spain and Canada, in which the International Court of Justice declared that it did not have jurisdiction over the dispute regarding the Canadian Navy’s seizure of a Spanish fishing vessel on the high seas pursuant to amended regulations extending Canada’s fisheries enforcement jurisdiction beyond its EEZ, but within the regulatory area of the Northwest Adantic Fisheries Organization. Canada had filed a reservation to its acceptance of the Court’s optional jurisdiction on May 10, 1994. Fisheries Jurisdiction (Spain v. Can.) (Int’l Ct.Justice Dec. 4, 1998). See Christopher C. Joyner & Alejandro Alvarez von Gustedt, The 1995 Turbot War: Lessons for the Law of the Sea, 11 Int’l J. Marine & Coastal L. 425 (1996).

⁷ A “common” resource is defined as any natural resource that is used (or is capable of being used) by at least two states.

⁸ The concept of “joint development” has not been understood or applied uniformly. The Conclusions and Recommendadons of the lawyers’ group at the Second Workshop on Geology and Hydrocarbon Potential in the South China Sea and Possibilities of Joint Development, held in Honolulu during August 1983, defined joint development as extending from unitization of shared resources to unilateral development of a shared resource beyond a stipulated boundary, and various gradations in between. See Masahiro Miyoshi, The Basic Concept of Joint Development of Hydrocarbon Resources on the Continental Shelf, 3 Int’l J. Estuarine L. 1,5, & Appendix II, at 17 (1988) [hereinafter Miyoshi, Basic Concept].

Townsend-Gault defines joint development as “a decision by [two or more countries] to pool any rights they may have over a given area and, to a greater or lesser degree, undertake some form of joint management for the purposes of exploring for and exploiting offshore minerals.” Ian Townsend-Gault, Joint Development of Offshore Mineral Resources—Progress and Prospects for the Future, 12 Nat. Resources F. 275, 275 (1988).

Lagoni restricts the scope of joint development to cooperation between states based on an agreement regarding the exploration for and exploitation of certain deposits, fields or accumulations of nonliving resources that either extend across a boundary or lie in an area of overlapping claims. See International Law Association [ILA], International Committee on the EEZ, Report on Joint Development of Non-Living Resources in the Exclusive Economic Zone at 2 (Rainer Lagoni, rapporteur, 1988) [hereinafter 1988 ILA Report].

Miyoshi also takes a restrictive view of joint development that limits it to an intergovernmental agreement, to the exclusion of joint ventures between a government and an oil company or consortia of private companies for capital participation. He therefore defines joint development as “[a]n inter-governmental arrangement of a provisional nature, designed for functional purposes of joint exploration for and/or exploitation of hydrocarbon resources of the sea-bed beyond the territorial sea.” Masahiro Miyoshi, The Joint Development of Offshore Oil and Gas in Relation to Maritime Boundary Delimitation 3 (International Boundaries Research Unit, Maritime Briefing No. 5, 1999) [hereinafter Miyoshi, Oil and Gas].

Finally, the research team of the British Institute of International and Comparative Law defines joint development as an agreement between two states to develop, so as to share jointly in agreed proportions by interstate cooperation and national measures, the offshore oil and gas in a designated zone of the seabed and subsoil of the continental shelf to which either or both of the participating states are entitled in international law. 1 Hazel Fox et al., Joint Development of Offshore Oil and Gas 45 (1989).

⁹ The term “transboundary” or “international” unitization as used here describes an agreement between states applying unitization procedures to a deposit located in a cross-border or overlapping claims area. For the purposes of this article, the joint development concept includes such transboundary or international unitization agreements. Unitization agreements per se have been defined by Taverne as agreements between two or more persons or groups of persons holding exploitation rights in common petroleum reservoirs by which these reservoirs will be exploited in an integrated manner, as a single unit. Bernard Taverne, An Introduction to the Regulation of the Petroleum Industry: Law, Contracts and Conventions 149 (1994). Lagoni defines unitization as the use of a single operator to manage a common petroleum deposit shared by two or more concessionaires. Rainer Lagoni, Oil and Gas Deposits Across National Frontiers, 73 AJIL 215, 224 (1979) (citing John C. Jacobs, Unit Operation of Oil and Gas Fields, 57 Yale L.J. 1207, 1210 (1947–48); and James E. Horigan, Unitization of Petroleum Reservoirs Extending Across Sub-Sea Boundary Lines of Bordering States in the North Sea, 7 Nat. Resources Law. 67, 73 (1974)).

¹⁰ Kwiatkowska notes that such transboundary resource deposit clauses are often modeled on the 1965 UK-Norway Agreement, in/ra note 12, and are found in a considerable number of maritime delimitation agreements. Barbara Kwiatkowska, Economic and Environmental Considerations in Maritime Boundary Delimitations, in International Maritime Boundaries 75, 87 n.49 (Jonathan I. Charney & Lewis M. Alexander eds., 1993) [hereinafter Maritime Boundaries]. For an earlier list of such provisions, see 1988 ILA Report, supra note 8, at 50–51 n.39. See also Hui Yu, Joint Development of Mineral Resources—An Asian Solution ? 1992 Asian Y.B. Int’l L. 87, 102 nn.73, 74.

¹¹ Writing in 1979, Lagoni found that more than half of the 60 delimitation agreements concluded since 1942 contained such clauses. Lagoni, supra note 9, at 233. More recendy, Kwiatkowska, supra note 10, identified 51 instances in agreements reported in 1 & 2 Maritime Boundaries, supra note 10. Colson notes that unitization provisions are not uncommon in continental shelf boundary agreements. He counts 36 of these provisions, as well as several other, more specific cooperative requirements in die maritime boundary agreements collected in id. David Colson, The Legal Regime of Maritime Boundary Agreements, in id. at 41, 55–56 nn. 70–77.

¹² Agreement Relating to the Delimitation of the Continental Shelf between the Two Countries, Mar. 10, 1965, UK-Nor., 1965 Gr. Brit. TS No. 71 (Cmnd. 2757), 551 UNTS 214. See D. H. Anderson, Norway–United Kingdom, Report No. 9-15, in Maritime Boundaries, supra note 10, at 1879.

¹³ Another example from the North Sea region, with almost identical wording, is the Agreement Relating to the Exploitation of Single Geological Structures Extending across the Dividing Line on the Continental Shelf under the North Sea, Oct. 6, 1965, UK-Neth., Art. 1, 1967 Gr. Brit. TS No. 24 (Cmnd. 3254). According to Taverne:

The wording of the article suggests that the fact that a reservoir crosses the dividing line is of itself not sufficient to trigger the obligation to co-operate in developing such a reservoir. The requirement is for it to be technically possible to exploit the one part of die reservoir from the other side of die dividing line. But it is not required that the straddling reservoir should be exploited as an unit…. The only firm condition imposed is apparently the condition that the proceeds of exploitation should be shared.

Taverne, supra note 9, at 155.

¹⁴ Agreement Relating to the Exploitation of the Frigg Field Reservoir and the Transmission of Gas Therefrom to the United Kingdom, May 10,1976, UK-Nor., 1977 Gr. Brit. TS No. 113 (Cmnd. 7043), 1098 UNTS 3. See J. C. Woodliffe, International Unitization of an Offshore Gas Field, 26 Int’l & Comp. L.Q. 338 (1977). Similar agreements relating to the Murchison and Statfjord Fields were also concluded by die United Kingdom and Norway on October 16, 1979, 1981 Gr. Brit. TS No. 39 (Cmnd. 8270) & No. 44 (Cmnd. 8282). The 1965 Anglo-Dutch Agreement, supra note 13, recendy yielded a similar unitization agreement. Agreement Relating to the Exploitation of the Markham Field Reservoirs and the Offtake of Petroleum Therefrom, May 26,1992, UK-Neth., 1993 Gr. Brit. TS No. 38 (Cmnd. 2254).

¹⁵ North Sea Continental Shelf (FRG/Den.; FRG/Nedi.), 1969 ICJ Rep. 3, 22, para. 20 (Feb. 20) [hereinafter North Sea Cases].

¹⁶ In die negotiations on the 1982 Convention, an Irish proposal attempted to formalize this presumption of the legitimacy of any continental shelf claim by prohibiting other states from carrying on exploration and exploitation activities in any areas that are claimed bona fide by any other state, except with diat state’s express consent. Ireland: Draft article on delimitation of areas of continental shelf between neighbouring States, 3 Third United Nations Conference on the Law of the Sea, Official Records 220, UN Sales No. E.75.V.5 (1974). However, Lagoni notes that the requirement of a bona fide claim could only be relevant if on its face a claim were not justified by existing international law. Rainer Lagoni, Interim Measures pending Maritime Delimitation Agreements, 78 AJIL 345, 357 (1984).

¹⁷ See Ian Townsend-Gault & William G. Stormont, Offshore Petroleum Joint Development Arrangements: Functional Instrument ? Compromise ? Obligation ? in The Peaceful Management of Transboundary Resources 51, 51 (Gerald H. Blake etal. eds., 1995) [hereinafter Peaceful Management].

¹⁸ The combined effect of Articles 57, 76(1) and 77 of the LOS Convention, supra note 1, provides all coastal state parties and arguably even non–state parties under customary international law with a legal claim to a continental shelf of at least 200 nautical miles from their coastal baselines, over which they exercise sovereign rights for the purpose of exploring it and exploiting its natural resources. This is because Articles 76(1) and 77 apparently accord these sovereign rights to all coastal states, not merely parties to the Convention. Wolfram notes that references to “States Parties,” “States” and even “all States” as having rights or obligations under the Convention seem to indicate that it creates or codifies rights and obligations for both state parties and nonparties—notwithstanding the generally accepted principle that a state is bound only by treaty law to which it has consented. Rüdiger Wolfram, The Legal Order for the Seas and Oceans, in Entry into Force of the Law of the Sea Convention: 1994 Rhodes Papers 161, 166–67 (Myron H. Nordquist & John Norton Moore eds., 1995). See also Nikos St. Skourtos, Effectsfor Parties and Non-Parties: The Impact ojtheLaw oftfie Sea Convention, mid. at 187.

¹⁹ Memorandum of Understanding on the Establishment of a Joint Authority for the Exploitation of the Resources in the Sea-bed in a Defined Area of the Continental Shelf of the Two Countries in the Gulf of Thailand, Feb. 21, 1979, Malaysia-Thail., 6 Energy 1355 (1981); and Agreement on the Constitution and Other Matters Relating to the Establishment of die Malaysia-Thailand Joint Authority, May 30, 1990, Malaysia-Thail. See David Ong, Thailand/Malaysia: The Joint Development Agreement 1990, 6 Int’l J. Estuarine & Coastal L. 57 (1991). For both texts, see id., Appendix 1, at 61, and Appendix 2, at 64. For background and the latest developments, see David M. Ong, The 1979 and 1990 Malaysia-Thailand Joint Development Agreements: A Model far International Legal Cooperation in Common Offshore Petroleum Deposits? 14 Int’l J. Marine & Coastal L. 207 (1999).

²⁰ Agreement concerningjoint Development of the Southern Part of the Continental Shelf Adjacent to the Two Countries, Feb. 5, 1974, Japan-S. Korea, in 4 New Directions in the Law of the Sea 117 (R. R. Churchill & Myron H. Nordquist eds., 1975) [hereinafter New Directions]. This situation was complicated by the conflicting claims of Taiwan, and later the People’s Republic of China, to the same continental shelf area.

²¹ Coastal state rights to exploit the adjacent continental shelf have their roots in the Truman Proclamation of 1945, which asserted that the natural resources of the seabed and subsoil of the continental shelf contiguous to the coasts of the United States belonged to the United States and were subject to its jurisdiction and control. Proclamation No. 2667, Policy of the United States with Respect to the Natural Resources of the Subsoil and Sea Bed of the Continental Shelf, Sept. 28,1945,10 Fed. Reg. 12,303 (1945).

²² See LOS Convention, supra note 1, Art. 77(2); and Convention on the Continental Shelf, Apr. 29,1958, Art. 2(2), 15 UST 471, 499 UNTS 311. See Report of the International Law Commission to the General Assembly, [1956] 2 Y.B. Int’l L. Comm’n 253, 264, Art. 68, UN Doc. A/CN.4/SER.A/1956/Add.1. See also Shigeru Oda, International Control of Sea Resources 162 (reprint 1989) (1963).

²³ See Ian Brownlie, Principles of Public International Law 215 (5th ed. 1998).

²⁴ See Oda, supra note 22, at 163. Article 2(2) of the 1958 Geneva Convention, supa note 22, established this concept for the first time as a positive rale of international law. It is now included almost verbatim in Article 77 (2) of the LOS Convention, supra note 1.

²⁵ Lagoni, supra note 9, at 238.

²⁶ As successively provided for in Article 2 of the 1958 Geneva Convention on the Continental Shelf, supra note 22, and Article 77 of the LOS Convention, supra note 1.

²⁷ See, e.g., North Sea Cases, 1969 ICJ Rep. at 22, para. 19 (holding that the sovereign rights of a coastal state exist ipso facto and ab initio by virtue of its sovereignty over the adjacent land territory). This case was decided by the application of customary international law, as Germany was not a party to the relevant international agreement, the Convention on the Continental Shelf. Id. at 28, para. 37.

²⁸ Arucle 2(3) of die 1958 Convention, supra note 22, now provided word forword in Article 77(3) of the LOS Convention, supra note 1. This rule has special force in respect of the so-called inner continental shelf, up to 200 nautical miles from die baseline, which coincides with the 200-nautical-mile EEZ limit (id., Art. 57).

²⁹ Townsend-Gault & Stormont, supra note 17, at 56.

³⁰ Contrary to what was envisaged in William T. Onorato, Apportionment of an International Common Petroleum Deposit, 26 Int’l & Comp. L.Q. 324,329 (1977).

³¹ 2 D. P. O’Connell, The International Law of the Sea 691 (1984). See also Townsend-Gault & Stormont, supra note 17, at 56.

³² See O’Connell, supra note 31, at 692.

³³ Nortfi Sea Cases, 1969 ICJ Rep. at 22, para. 20, cited in id at 693. Later in the same Judgment, the Court held that the appurtenance of a given continental shelf area to one state or another in no way governs the precise delimitation of its maritime boundaries, any more than uncertainty over land boundaries can affect territorial rights. Id at 32, para. 46.

³⁴ William T. Onorato, Apportionment of an International Common Petroleum Deposit, 17 Int’l & Comp. L.Q. 85 (1968).

³⁵ Id. at 85.

³⁶ See, e.g., Prosper Weil, The Law of Maritime Delimitation—Reflections 9–14 (1989).

³⁷ Under Article 76(1) of the LOS Convention, the continental shelf of a coastal state extends to the outer edge of the continental margin, subject to the limits prescribed in Article 76 (5) and (6), or to a distance of 200 nautical miles where the outer edge of the continental margin does not extend that far. The notion of natural prolongation has therefore been disregarded where the distance claimed is not more than 200 nautical miles. As Reid notes, “[W]here the continental shelf does not extend beyond 200 nautical miles the coastal state is [nevertheless] entided to exercise jurisdiction over the seabed regardless of its nature, out to 200 nautical miles.” Peter C. Reid, Petroleum Development in Areas of International Seabed Boundary Disputes: Means for Resolution., 8 Oil & Gas L. & Tax’n Rev. 214, 215 (1984–85).

³⁸ R. R. Churchill, Joint Development Zones: International Legal Issues, in 2 Foxet Al., supra note 8, at 55,56 (1990).

³⁹ Nico Schrijver, Sovereignty over Natural Resources: Balancing Rights and Duties 338 (1997).

⁴⁰ 1 Fox et al., supra note 8, at 39.

⁴¹ Part VI of the LOS Convention, supra note 1 (Arts. 76–85), especially Art. 77. Certain writers contend, however, that the duty to conserve, or at least efficiendy manage, the mineral resources of the continental shelf was an implicit element in the evolution of the continental shelf regime under general international law, even if not explicidy provided for in subsequent multilateral conventions on the law of the sea. For example, Townsend-Gault argues that resource conservation (albeit on a unilateral basis) lay at the heart of the continental shelf doctrine under international law: “Jurisdiction was extended … for the purposes of [petroleum] exploitation in a controlled and properly managed manner.” Ian Townsend-Gault, Regional Maritime Cooperation Post-UNCLOS/UNCED: Do Boundaries Matter Any More? in International Boundaries and Environmental Security: Frameworks for Regional Cooperation 3, 6 (Gerald Blake et al. eds., 1997). The lack of explicit conservation and management requirements is most obvious in relation to sedentary species, sovereign rights to which are explicidy provided for under the continental shelf regime by Article 77(4) and just as explicitly excluded from the EEZ regime by Article 68 of the LOS Convention.

⁴² Part V of the LOS Convention, supra note 1 (Arts. 55–75).

⁴³ Id., Art. 56(1)(a). See also Article 61, which reiterates the obligation to conserve and manage the living resources of the EEZ.

⁴⁴ See id., Art. 123.

⁴⁵ Douglas M. Johnston, The Theory and History of Ocean Boundary-Making 227–29 (1988) (citing Oran R. Young, Resource Regimes: Natural Resources and Social Institutions passim (1982)).

⁴⁶ The rule of capture has been defined in terrestrial terms as follows: the right to drill for and produce oil and gas from a particular tract of land even though doing so will drain the hydrocarbon concerned from beneath the land of another party. See Joseph W. Morris, The North Sea Continental Shelf: Oil and Gas Legal Problems, 2 Int’l Law. 191, 206 (1967). This rule is derived from the early municipal case law of several oil-producing jurisdictions, notably in the United States. According to Onorato, supra note 34, at 90, “Under this rule, tide to petroleum was determined solely by ownership gained … byway of unregulated and often wasteful extraction.”

⁴⁷ Brownlie, supra note 23, at 215.

⁴⁸ The LOS Convention transforms sovereignty by disaggregating the concept into bundles of rights ranging from “sovereign rights” (Arts. 77(1), 56(1) (a)) to “exclusive right” (Arts. 60, 81), “jurisdiction and control” (Art. 94) and “jurisdiction” (Art. 79(4)), which may be shared with other states in the same spatial dimension, such as the continental shelf and the EEZ. See Elisabeth Mann Borgese, Ocean Governance and the United Nations 17–18 (Dalhousie University Centre for Foreign Policy Studies, 1995).

⁴⁹ One successful attempt was the adoption of General Assembly Resolution 3016 (XXVII), Permanent Sovereignty over Natural Resources of Developing Countries, UN GAOR, 27th Sess., Supp. No. 30, at 48, UN Doc. A/8730 (1972), which passed by 102-0, with 22 abstentions (including developed and developing countries) on December 18,1972. See Schrijver, supra note 39, at 90–92.

⁵⁰ Morris, supra note 46, at 210, affirms the applicability of an inferred rule of capture under international law but notes that within the North Sea context, UK and Norwegian domestic regulations had replaced this rule with that requiring the unit(ization) or cooperative development of adjoining license tracts. Bundy notes that, in the absence of an agreement to the contrary, the exploitation of common hydrocarbon reserves is still based largely on the rule of capture; a state or corporate licensee is free to maximize production from its side of the boundary line, notwithstanding the policies of the neighboring states sharing the same field. Rodman R. Bundy, Natural Resource Development (Oil and Gas) and Boundary Disputes, in Peaceful Management, supra note 17, at 23, 24.

⁵¹ Miyoshi notes that a group of lawyers specializing in the international law of the sea and energy at the Third Workshop on Joint Exploration and Development of Offshore Hydrocarbon Resources in Southeast Asia, held in Bangkok from February 25 to March 1, 1985 [hereinafter Third Workshop], broadly agreed that no international rule of capture exists, citing a handwritten memorandum entitled “Summary Thoughts” byjon Van Dyke, chairman of the final session. Miyoshi, Basic Concept, supra note 8, at 6, and Appendix 3, at 18.

⁵² In Memorandum on the Regime of the High Seas, prepared by the UN Secretariat for the International Law Commission, [1950] 2Y.B. Int’l L. Comm’n 67, 112, para. 337, UN Doc. A/CN.4/SERA/1950/Add.1, cited in M. W. Mouton, The Continental Shelf, 85 Recueil des Cours 347, 421 (1954 I).

⁵³ Lagoni, supra note 9, at 217 (quoting Northcutt Ely, The Conservation of Oil, 51 Harv. L. Rev. 1209, 1219 (1937–38)). Commenting on the same problem, Townsend-Gault notes that unilateral exploitation may cause “long-term difficulties for all, for example, by leaving a sizeable residue in the reservoir, recovery of which is not economically viable.” Ian [Townsend-]Gault, The Frigg Gas Field, 3 Marine Pol’y, 302, 303 (1979). Preservation of the unity of a deposit assumes even greater significance in light of the obligation of mutual restraint, infra part V.

⁵⁴ For example, the Anglo-Norwegian and Anglo-Dutch continental shelf delimitation treaties of the mid-1960s, supra notes 12,13. See also Kwiatkowska, supra note 10, at 87 n.49; Colson, supra note 11, at 55–56 nn.70–77; 1988 ILA Report, supra note 8, at 50–51.

⁵⁵ See Onorato, supra note 30, at 325; Lagoni, supra note 9, at 216–18.

⁵⁶ As Swarbrick notes, “Apportionment of reserves is based on technical considerations which can be highly uncertain, especially in the early stages of the development of an oil or gas field.” He therefore urges that this uncertainty be taken into account in early decisions on apportionment. Richard E. Swarbrick, Oiland Gas Reservoirs Across Ownership Boundaries: The Technical Basis/or Apportioning Reserves, in Peaceful Management, supmnote 17, at 41, 49–50.

⁵⁷ See Townsend-Gault, supra note 41, at 6.

⁵⁸ See Onorato, supra note 34, at 89–90.

⁵⁹ Id. at 91.

⁶⁰ Id. at 92.

⁶¹ Id.

⁶² Charles Robson, Transboundary PetroleumReservoirs: Legallssues and Solutions, in Peaceful Management, supra note 17, at 3, 6.

⁶³ Id. at 8.

⁶⁴ Lagoni, supra note 9, at 239.

⁶⁵ North Sea Cases, 1969 ICJ Rep. at 22, para. 19; Convention on the Continental Shelf, supra note 22, Art. 2; LOS Convention, supra note 1, Art. 77. See also part II supra; 2 O’Connell, supra note 31, at 691–93.

⁶⁶ Lagoni, supra note 9, at 239.

⁶⁷ See id. at 236 (citing Helsinki Rules on the Uses of the Waters of International Rivers, Art. 4, 51 ILA, Conference Report 484 (1966), now provided in part II (Arts. 5–10) of the Convention on the Law of the Non-Navigational Uses of International Watercourses, May 21, 1997, UN Doc. A/51/869, 36 ILM 700 (1997)). See also the bilateral agreements cited by Onorato, supra note 34, at 95–96.

⁶⁸ Miyoshi, Basic Concept, supra note 8, at 8.

⁶⁹ Byers, for example, noted recently that

many non-industrialised States and a significant number of writers have asserted that resolutions and declarations are important forms of State practice which are potentially creative, or at least indicative, of rules of customary international law. The International Court of Justice appears to have reinforced this view by accepting, in its judgment in the 1986 Nicaragua Case (Merits), that a series of United Nations General Assembly resolutions played a major role in the development of rules of customary international law prohibiting intervention and aggression. However, these assertions have, in turn, been resisted by many powerful States and some writers.

Michael Byers, Custom, Power and the Power of Rules: International Relations and Customary International Law 135 (1999).

⁷⁰ See Declaration on Principles of International Law concerning Friendly Relations and Co-operation among States in accordance with the Charter of the United Nations, GA Res. 2625 (XXV), UN GAOR, 25th Sess., Supp. No. 28, at 121, UN Doc. A/8028 (1970) (adopted without a vote).

⁷¹ GA Res. 3281 (XXIX), UN GAOR, 29th Sess., Supp. No. 30, at 50, UN Doc. A/9030 (1974) (emphasis added).

⁷² The charter was adopted by 120-6, with 10 abstentions. The countries voting against the charter were Belgium, Denmark, the Federal Republic of Germany, Luxembourg, the United Kingdom and the United States. The abstaining states were Austria, Canada, France, Ireland, Israel, Italy, Japan, the Netherlands, Norway and Spain.

⁷³ A separate vote was taken on Article 2(2) (c), which allowed the nationalization or expropriation of foreign property. The majority in favor was 104-16, with 6 abstentions. See D. J. Harris: Cases and Materials on International Law 550 (5th ed. 1998).

⁷⁴ Nevertheless, this article was passed by a separate vote of 100-8, widi 28 abstentions, the largest number of abstentions on the 1974 charter; the vote on this article reflected the difficulty of establishing a legal regime for shared natural resources that does not impinge on the principle of permanent sovereignty over natural resources. See Schrijver, supra note 39, at 110, 131 & 337 n. 112.

⁷⁵ See Judo Umarto Kusumowidagdo, Consultation Clauses as Means for Providing for Treaty Obedience 145–46 (1981) (“Either tacidy or expressly, all treaties of common interests in die use of common [re]sources anticipate the operation of the rule of consultation prior to action.”).

⁷⁶ Draft Principles of Conduct in the Field of the Environment for the Guidance of States in the Conservation and Harmonious Utilization of Natural Resources Shared by Two or More States, UNEP Doc. GC Dec. No. 6/14, reprinted in UN Doc. A/33/25, at 154 (1978), 17 ILM 1097 (1978), adopted by consensus on May 19, 1978, although three Latin American states (Brazil, Colombia and Mexico) declared that they were unable to join the consensus. See 17 ILM at 1092–93.

⁷⁷ GA Res. 34/186, UN GAOR, 34th Sess., Supp. No. 46, at 123, UN Doc. A/34/46 (1979).

⁷⁸ Id, para. 3. See Schrijver, supra, note 39, at 132–33.

⁷⁹ Schrijver, supra note 39, at 338.

⁸⁰ Article 122 of the LOS Convention, supra note 1, provides that an “enclosed or semi-enclosed sea” means, inter alia, a sea consisting entirely or primarily of the territorial seas and exclusive economic zones of two or more coastal states. For the agreements, see, regarding Malaysia and Thailand, supra note 19; and Memorandum of Understanding for the exploration and exploitation of petroleum in the Gulf of Thailand, June 5, 1992, Malaysia-Vietnam, in Ted L. McDorman, Malaysia-Vietnam, Report No. 5-19,3 Maritime Boundaries, supranote 10, at 2335, 2341 (1998); Treaty on the Zone of Cooperation in an Area between the Indonesian Province of East Timor and North Australia, Dec. 11, 1989, Austl.-Indon., 29ILM 469 (1990), reprinted in, R. V. Prescott, Australia-Indonesia, Report No. 6-2(5), Maritime Boundaries, supra note 10, at 1245.

⁸¹ Namely, the Frigg, Statfjord and Murchison Field Agreements, supra note 14, made pursuant to Article 4 of the 1965 Continental Shelf Agreement between the United Kingdom and Norway; and the Markham Field Agreement, supra note 14, made pursuant to Article 1 of the 1965 Continental Shelf Agreement between the United Kingdom and the Netherlands.

⁸² For example, Agreement Concerning the Delimitation of the Continental Shelf in the Persian Gulf, Feb. 22, 1958, Bahr.-Saudi Arabia, United Nations, National Legislation and Treaties Relating to the Law of the Sea 409, UN Doc. ST/LEG/SER.B/16, UN Sales No. E/F.74.V.2 (1974) [hereinafter Legislation and Treaties], 5 New Directions, supra note 20, at 207 (R. R. Churchill, Myron H. Nordquist & S. Houston Lay eds., 1977); Agreement Relating to the Partition of the Neutral Zone, July 7,1965, Kuwait–Saudi Arabia, 4 ILM 1134 (1965); Agreement on the Setdement of Maritime Boundary Lines and Sovereign Rights over Islands, Mar. 20, 1969, Qatar–Abu Dhabi, Legislation and Treaties, supra, at 403, and in Robert F. Pietrowski, Jr., Qatar–United Arab Emirates (Abu Dhabi), Report No. 7-9, Maritime Boundaries, supra note 10, at 1541; Memorandum of Understanding, Nov. 18,1971, Iran-Sharjah, reprinted in Ali A. El-Hakim, The Middle Eastern States and the Law of the Sea 208 (1979).

⁸³ See M. L. Pecoraro, The Concept of Enclosed and Semi-Enclosed Seas in the New Law of the Sea, 1989 Y.B. II Università degli Studi di Roma, Dipartimento di diritto pubblico 369, 379.

⁸⁴ See Gunther Jaenicke, Cooperation in the Baltic Sea, in The Law of the Sea in the 1980s: Proceedings 493, 509 (Choon-ho Park ed., 1983).

⁸⁵ LOS Convention, supra note 1, Art. 123(a), (b) & (c), respectively.

⁸⁶ See Budislav Vukas, Commentary, in The Law of the Sea in the 1980s, supra note 84, at 531. This view is endorsed by Pecoraro, who also interprets Article 123 as conferring a right on the coastal states of a semienclosed sea to safeguard their individual and collective interests in the management and conservation of the living and “non-living resources” there. The obligation to cooperate must be fulfilled by means of positive action and measures that do not cause detriment to or impinge upon the rights of the other coastal states to enjoy the common resources. However, Pecoraro does not include common offshore petroleum deposits widiin the meaning of “non-living resources.” Pecoraro, supra note 83, at 378–79.

⁸⁷ Lagoni, Commentary, in The Law of the Sea in the 1980s, supra note 84, at 520.

⁸⁸ See Janusz Symonides, The Legal Status of the Enclosed and Semi-Enclosed Seas, 1984 Ger. Y.B. Int’l L. 315, 327.

⁸⁹ LOS Convention, supra note 1, Art. 83(1).

⁹⁰ Id., Art. 83(3).

⁹¹ See Kwiatkowska, supra note 10, at 87 n.49; and Colson, supra note 11, at 55–56 nn.70–77. Examples of Southeast Asian agreements on delimitation of the continental shelf that incorporate such clauses can be found in David Ong, Southeast Asian State Practice on the Joint Development of Offshore Oil and Gas Deposits, in Peaceful Management, supra note 17, at 77, 83–84. See also Kriangsak Kittichaisaree, The Law of the Sea and Maritime Boundary Delimitation in South-East Asia 69–70 (1987).

⁹² Significantly, Article 83 is specifically referred to in the Preamble to the 1989 Timor Gap Treaty between Indonesia and Australia, supra note 80.

⁹³ See Townsend-Gault, supra note 41, at 5–6.

⁹⁴ Id. at 5. See aftoLagoni, supra note 16, at 358.

⁹⁵ See D. H. Anderson, Strategies for Dispute Resolution: Negotiating Joint Agreements, in Boundaries and Energy: Problems and Prospects 473, 476 (Gerald Blake et al. eds., 1998).

⁹⁶ LOS Convention, supra note 1, Art. 83(2).

⁹⁷ Id., Art. 298(1) (a) (i).

⁹⁸ Article 33(1) of the UN Charter, for example, provides that parties to any dispute are required to seek a solution, inter alia, by negotiation.

⁹⁹ For example, in the North Sea Cases, 1969ICJ Rep. at 47, para. 85, the ICJ held that the states concerned were obliged to enter into negotiations with a view to arriving at an agreement, and that these negotiations had to be meaningful. Indeed, Goldie suggests that this requirement of good faith denotes an objective standard by which to evaluate a state’s conduct. L. F. E. Goldie, Delimiting Continental Shelf Boundaries, in Limits to National Jurisdiction over the Sea 3, 18 (George T. Yates III & John Hardin Young eds., 1974).

¹⁰⁰ These equitable principles include, inter alia, the general configuration of the relevant coastline, the physical and geological structure, and availability of natural resources in the disputed area, as well as a reasonable degree of proportionality between the extent of the continental shelf area appertaining to the coastal state and the length of its coast measured in the general direction of the coasdine. See North Sea Cases, 1969 ICJ Rep. at 54–55, para. 101(D).

¹⁰¹ LOS Convention, supra note 1, Art. 142. One of these parties will be the International Sea-Bed Authority, which has overall responsibility for the deep seabed regime. See id., Arts. 137(2), 156–58.

¹⁰² Id., Art. 142(1).

¹⁰³ Id., Art. 142(2).

¹⁰⁴ Id.

¹⁰⁵ Yu, supra note 10, at 101.

¹⁰⁶ North Sea Cases, 1969 ICJ Rep. at 52, para. 97. See also Continental Shelf (Tunis./Libya), 1982 ICJ Rep. 18, 77–78, para. 107 (Feb. 24) [hereinafter Tunisia/Libya], where the ICJ was prepared to regard the presence of oil wells in an area to be delimited as “an element to be taken into account in the process of weighing all relevant factors to achieve an equitable result,” quoted in 2 O’Connell, supra note 31, at 712.

¹⁰⁷ The UK-Norwegian Continental Shelf Agreement, supranote 12, Art. 4.

¹⁰⁸ Supplementary Agreement to the Treaty concerning Arrangements for Co-operation in the Ems Estuary (Ems-Dollard Treaty, 1960), May 14,1962, Neth.-FRG, 509 UNTS 140.

¹⁰⁹ North Sea Cases, 1969 ICJ Rep. at 52–53, para. 97.

¹¹⁰ Id. at 52, para. 99.

¹¹¹ For example, the Agreement between Kuwait and Saudi Arabia relating to the Partition of the Neutral Zone, supra note 82; and the Agreement on the Continental Shelf between Bahrain and Saudi Arabia, supra note 82.

¹¹² North Sea Cases, 1969 ICJ Rep. at 82 (Jessup, J., sep. op.).

¹¹³ Id.

¹¹⁴ R. R. Churchill & A. V. Lowe, The Law of the Sea 10 (2d rev. ed. 1988).

¹¹⁵ ICJ Statute Art. 38 (1) (c). A similar point is made by Onorato, supra note 34, at 89; and Onorato, supra, note 30, at 330–31.

¹¹⁶ Conciliation Commission on the Continental Shelf Area between Iceland and Jan Mayen, Report and Recommendations to the Governments of Iceland and Norway, 20 ILM 797 (1981).

¹¹⁷ Id. at 826.

¹¹⁸ Id. at 839.

¹¹⁹ Agreement on the Continental Shelf between Iceland and Jan Mayen, Oct. 22,1981, Ice.-Nor., 21 ILM 1222 (1982). See also D. H. Anderson, Iceland-Nmway (Jan Mayen), Report No. 9-4, in Maritime Boundaries, supra note 10, at 1755.

¹²⁰ Agreement on the Continental Shelf, supra note 119, Art. 3.

¹²¹ Id., Art. 4.

¹²² Id.

¹²³ Agreement on the Continental Shelf, supra note 119, Arts. 5, 6.

¹²⁴ Id., Arts. 5 & 6, respectively.

¹²⁵ Id., Art. 5.

¹²⁶ Id., Art. 6.

¹²⁷ Id., Art. 5.

¹²⁸ Id., Art. 8.

¹²⁹ Id. See 1 Fox et al., supra note 8, at 63.

¹³⁰ Tunisia/Libya, 1982 ICJ Rep. at 18.

¹³¹ See 1 Fox et al., supra note 8, at 64.

¹³² Miyoshi, Oil and Gas, supra note 8, at 35–36; see also Tullio Scovazzi, Libya-Tunisia, Report No. 8-9, in Maritime Boundaries, supra note 10, at 1663, 1664.

¹³³ See 1 Fox et al., supra note 8, at 64.

¹³⁴ Tunisia/Libya, 1982 ICJ Rep. at 320–23 (Evensen, J., dissenting). Judge Evensen was also a member of the Norway-Iceland Conciliation Commission that recommended a similar solution to the Jan Mayen dispute, later provided for in the 1981 Agreement, supranote 119.

¹³⁵ Tunisia/Libya, 1982 ICJ Rep. at 320–23 (Evensen, J., dissenting).

¹³⁶ Id.

¹³⁷ As opposed to the specific rule requiring positive or proactive cooperation with a view to joint development espoused by Onorato, supra note 30, at 332–37.

¹³⁸ See 1988 ILA Report, supra note 8, at 1.

¹³⁹ A chronological, but nonexhaustive, list of these agreements includes the following: Agreement concerning die Delimitation of the Continental Shelf in the Persian Gulf, between Bahrain and Saudi Arabia, supra note 82; Agreement concerning the Working of Common Deposits of Natural Gas and Petroleum, Jan. 23, 1960, Czech Rep.-Aus., 495 UNTS 134; Supplementary Agreement concerning Arrangements for Co-operation in the Ems Estuary, between the Netherlands and Germany, supra note 108; Agreement Relating to Partition of the Neutral Zone, between Kuwait and Saudi Arabia, supranote 82; Agreement on the Settlement of Maritime Boundary Lines and Sovereign Rights over Islands, between Qatar and Abu Dhabi, supra note 82; Memorandum of Understanding, between Iran and Sharjah, supra note 82; Convention on the Delimitation of the Continental Shelf of the Two States in the Bay of Biscay, Jan. 29, 1974, Fr.-Spain, Legislation and Treaties, supra note 82, at 445, UN Doc. ST/LEG/SER.B/19, UN Sales No. E/F.80.V.3 (1980), 5 NEW DIRECTIONS, supra note 20, at 251; Agreement concerning Joint Development of the Southern Part of the Continental Shelf Adjacent to the Two Countries, between Japan and Soudi Korea, supra note 20; Agreement Relating to the Joint Exploitation of the Natural Resources of the Sea-bed and Sub-soil of the Red Sea in the Common Zone, May 16,1974, Sudan–Saudi Arabia, Legislation and Treaties, supra, at 452, UN Doc. ST/LEG/SER.B/18, UN Sales No. E/F.76.V.2 (1976), 5 New Directions, supra, at 393; Agreement Relating to the Exploitation of die Frigg Field Reservoir and the Transmission of Gas Therefrom to the United Kingdom, between die United Kingdom and Norway, supra note 14; Memorandum of Understanding on die Establishment of a Joint Audiority for the Exploitation of the Resources in the Sea-bed in a Defined Area of die Continental Shelf of the Two Countries in the Gulf of Thailand, between Malaysia and Thailand, supra note 19; Agreement on the Constitution and Other Matters Relating to the Establishment of the Malaysia-Thailand Joint Authority, between Malaysia and Thailand, supra note 19; Agreement on the Continental Shelf between Iceland and Jan Mayen, between Iceland and Norway, supra note 119; (Aden) Agreement for the Exploitation of (and Investment in) die Joint Area between the Two Sectors of Yemen, Nov. 19, 1988, Yemen Arab Republic-People’s Democratic Republic of Yemen, in Yemen Arab Republic, Bureau of Unity Affairs, United Yemen 239 (3d series of Official Documents on Yemeni Unification, 1989) (in Arabic), see William T. Onorato, Joint Development in the International Petroleum Sector: The Yemen Variant, 39 Int’l & Comp. L.Q. 653 (1990); Treaty on the Zone of Cooperation in an Area between die Indonesian Province of East Timor and North Australia, between Australia and Indonesia, supra note 80; Memorandum of Understanding for the exploration and exploitation of petroleum in the Gulf of Thailand, between Malaysia and Vietnam, supra note 80; Maritime Delimitation Treaty, Nov. 12, 1993, Jam.-Colom., in Kaldone G. Nweihed, Colombia-Jamaica, Report No. 2-18, Maritime Boundaries, supra note 10, at 2179,2200 (1998); Management and Co-operation Agreement, Oct. 14, 1993, Sen.-Guinea-Bissau, and Protocol of Agreement relating to the Organization and Operation of die Agency for Management and Co-operation, June 12,1995, Sen.-Guinea-Bissau, Law Sea Bull., July 1996, at 40 & 42, respectively, and in J. R. Victor Prescott, Guinea-Bissau-Senegal, Report No. 4-4(4) & (5), Maritime Boundaries, supra, at 2251, 2257; Joint Declaration on Co-operation over Offshore Activities in the South West Adantic, Sept. 27, 1995, Arg.-UK, 35 ILM 301 (1996), reprinted in 11 Int’l J. Marine & Coastal L. 113 (1996), see R. R. Churchill, Falkland Islands—Maritimejurisdiction and Co-operative Arrangements with Argentina, 46 Int’l & Comp. L.Q. 463 (1997).

¹⁴⁰ Specifically, the Nordi Sea, the Middle East, and the East and Southeast Asian regions. See die list of joint development and transboundary unitization agreements, supra note 139.

¹⁴¹ 1 Fox et al., supra note 8, at 115.

¹⁴² Id. at 149, 152.

¹⁴³ Agreement between Bahrain and Saudi Arabia, supra note 82. See Robert F. Pietrowski, Jr., Bahrain-Saudi Arabia, Report No. 7-3, in Maritime Boundaries, supra note 10, at 1489.

¹⁴⁴ Agreement between Bahrain and Saudi Arabia, supra note 82, Art. 1.

¹⁴⁵ Id., Art. 2.

¹⁴⁶ Id.

¹⁴⁷ Agreement between Qatar and Abu Dhabi, supra note 82. For commentary, see Yu, supra note 10, at 92–93; and 2 Fox et al., supra note 8, at 55–56.

¹⁴⁸ Agreement between Qatar and Abu Dhabi, supra note 82, Art. 6.

¹⁴⁹ Id., Art. 7.

¹⁵⁰ Treaty between Australia and Indonesia, supra note 80.

¹⁵¹ Id., Art. 4(1) (b) & (2) (b), respectively.

¹⁵² Agreement between Japan and South Korea, supra note 20. See Choon-ho Park, Japan-South Korea, Report No. 5-12, in Maritime Boundaries, supra note 10, at 1065.

¹⁵³ Delineated by Article II(1) of the Agreement between Japan and South Korea, supra note 80, and encompassing some 24, 101 square nautical miles.

¹⁵⁴ Id., Arts. III(1), IV(1) & V(1), respectively.

¹⁵⁵ Id., Arts. V(1)(b), VI.

¹⁵⁶ Id., Art. V(2). Approval is deemed to have been implicitly given unless one of the parties explicitly disapproves the operating agreement within two months of its submission to them for approval. See also 1 Fox et al., supra note 8, at 58, 116–32.

¹⁵⁷ Agreement between Japan and South Korea, supra note 20, Art. XXIV.

¹⁵⁸ Id., Art. XXV. See also Miyoshi, Oil and Gas, supra note 8, at 14, 44.

¹⁵⁹ Convention between France and Spain, supra note 152.

¹⁶⁰ Id., Art. 3.

¹⁶¹ Id., Annex II, para. 2.

¹⁶² Id., paras. 5, 6.

¹⁶³ Memorandum of Understanding between Malaysia and Vietnam, supra note 80, Art. 3(a).

¹⁶⁴ Id., Art. 3(b).

¹⁶⁵ Id.

¹⁶⁶ Maritime Delimitation Treaty between Jamaica and Colombia, supra note 139, Art. 3(1).

¹⁶⁷ Id., Art. 3(2), (3).

¹⁶⁸ Id., Art. 4(1).

¹⁶⁹ Id., Art. 4(3).

¹⁷⁰ Argentina-UKJoint Declaration, supra note 139, paras. 2(a), 3. The two states formally established the Joint Commission at a meeting in Buenos Aires, held from February 29 to March 1, 1996.

¹⁷¹ Id., para. 4(a), (b) & (c).

¹⁷² The coordinates of these areas are provided in an annex to the 1995 Joint Declaration.

¹⁷³ Argentina-UK Joint Declaration, supra note 139, para. 4(d).

¹⁷⁴ Id., para. 4(b) (i–v).

¹⁷⁵ Id., para. 2.

¹⁷⁶ Id., para. 7.

¹⁷⁷ See T. W. Wälde & Andrew McHardy, Introductory Note, 35 ILM 301, 302 (1996).

¹⁷⁸ Agreement between Kuwait and Saudi Arabia, supra note 82, Arts. IV and VI, read together.

¹⁷⁹ See 1 Fox et al., supra note 8, at 55, 132. See also Isa Huneidi, The Saudi/Kuwait joint development areas of the Neutral Zone, onshore and offshore, in 2 id, at 77, 84–86; Yu, supra note 10, at 92 (citing Arts. 4, 8 of the Agreement, supra note 82).

¹⁸⁰ Agreement between the then Yemen Arab Republic and die People’s Democratic Republic of Yemen (now unified as the Republic of Yemen), supranote 139. Aden was a part of the People’s Democratic Republic of Yemen.

¹⁸¹ See Onorato, supr anote 139, at 656–58 (citing part 2, Art. 7 of the Yemen Agreement, supranote 139).

¹⁸² See Miyoshi, Oil and Gas, supra note 8, at 43–44.

¹⁸³ Agreement between Sudan and Saudi Arabia, supra note 139.

¹⁸⁴ Id., Art. VII(d).

¹⁸⁵ For the 1979 Memorandum of Understanding and the 1990 Agreement between Malaysia and Thailand, see supra note 19.

¹⁸⁶ Treaty between Australia and Indonesia, supra note 80, Arts. 5 & 7, respectively.

¹⁸⁷ Article 7(1) of the 1990 Malaysia-Thailand Agreement, supra note 19, and Article 3(1) of the Australia-Indonesia Treaty, supra note 80, respectively.

¹⁸⁸ Article 1(1) of the 1990 Malaysia-Thailand Agreement, supra note 19, and Article 7(2) of the Australia-Indonesia Treaty, supra note 80, respectively.

¹⁸⁹ Article 7(2) (e) of the 1990 Malaysia-Thailand Agreement, supra note 19, and Article 3(2) of the Australia-Indonesia Treaty, supra note 80, respectively.

¹⁹⁰ Article 8 of the 1990 Malaysia-Thailand Agreement, supra note 19, and Articles 3(1), (2) & 8, and Annexes B & C of the Australia-Indonesia Treaty, supra note 80, respectively. In production-sharing contracts, ownership of the resources remains vested in the host country or its national oil company and the contractor normally acquires title at an agreed export or delivery point. On the other hand, a concession is usually a large, defined geographical area as to which a state grants exclusive rights to explore for and exploit petroleum resources to a private (usually foreign) oil company. See also Kamal Hossain, Choice of Petroleum Development Regime in Joint Development of Offshore Oil and Gas, in 2 Fox et al., supra note 8, at 72.

¹⁹¹ Management and Co-operation Agreement between Senegal and Guinea-Bissau, and Protocol to the Agreement, supra note 139.

¹⁹² Renamed and launched in Bissau during a visit by the Senegalese President on February 14, 1996.

¹⁹³ Agreement between Senegal and Guinea-Bissau, supra note 139, Art. 4.

¹⁹⁴ Id, Art. 2.

¹⁹⁵ Protocol to Senegal–Guinea-Bissau Agreement, supra note 139, Art. 23.

¹⁹⁶ Or, as Mendelson puts it more broadly, “we seek to identify the types of procedure which, if carried out by authorized actors, create law for members of the society in question.” Maurice Mendelson, The Subjective Element in Customary International Lam, 1995 Brit. Y.B. Int’l L. 177, 178.

¹⁹⁷ As unsuccessfully argued by Colombia in the Asylum case (Colom./Peru), Judgment, 1950 ICJ Rep. 266, 276–77 (Nov. 20), where the Court held that a “general practice accepted as law” could occur at a regional or local level between a few states or just two states in their relations inter se. Such a local custom was found to exist between Portugal and India in Right of Passage over Indian Territory (Port. v. India), Judgment, 1960 ICJ Rep. 6, 39–40 (Apr. 12).

¹⁹⁸ See Fisheries case (UK v. Nor.),Judgment, 1951 ICJ Rep. 116 (Dec. 18).

¹⁹⁹ Military and Paramilitary Activities in and against Nicaragua (Nicar. v. U.S.), Merits, 1986 ICJ Rep. 14, 86, para. 186 (June 27) [hereinafter Nicaragua case].

²⁰⁰ North Sea Cases, 1969 ICJ Rep. at 43, para. 74.

²⁰¹ Anderson, supra note 95, at 474 (citing Introduction to Peaceful Management, supra note 17, at xvi).

²⁰² Compare the view of Mendelson, supra note 196, at 204, that in “standard” cases involving the application of a purported rule of customary international law, it is unnecessary to prove the existence of opinio juris. In this writer’s view, however, the specific situation described here would be included in the category of cases where the conduct in question is ambiguous as to its legal import and would therefore fall outside the scope of Mendelson’s standard case.

²⁰³ Brownlie, supra note 23, at 7.

²⁰⁴ Mendelson, supra note 196, at 180, notes that the International Court has given little guidance on the issue and, moreover, betrays a lack of consistency in its own practice, frequently coming to its conclusions without discussion of eitfier the material (state practice) or die subjective (opinio juris) elements of customary international law.

²⁰⁵ Notably, in the Nicaragua case, 1986 ICJ Rep. at 99–100, para. 188, and 106, para. 202, respectively, when die Court presumed that opinio juris regarding the principles relating to the nonuse of force and nonintervention under customary international law pertained to relations between the parties rather dian subject it to a strict burden of proof. See also Mendelson, supra note 196, at 204–05. The Court’s reliance on opinio juris to circumvent and thus marginalize a history of state practice contrary to die articulation of a possible customary rule of nonintervention is also noted by Byers, supra note 69, at 133.

²⁰⁶ S.S. Lotus (Fr. v. Turk.), 1927 PCIJ (ser. A) No. 10.

²⁰⁷ As regards the practice of states to abstain from exercising their criminal jurisdiction within the high seas over a crime committed aboard a foreign-flagged vessel, the Court held that “only if such abstention were based on their being conscious of having a duty to abstain would it be possible to speak of an international custom.” Id. at 27.

²⁰⁸ North Sea Cases, 1969 ICJ Rep. at 44, para. 77. As the Court noted:

[E]ven if these instances of action by non-parties to the Convention were much more numerous than they in fact are, they would not, even in the aggregate, suffice in themselves to constitute the opinio juris;—for, in order to achieve this result, two conditions must be fulfilled. Not only must the acts concerned amount to settled practice, but they must also be such, or be carried out in such a way, as to be evidence of a belief that this practice is rendered obligatory by the existence of a rule of law requiring it. The need for such a belief, i.e., the existence of a subjective element, is implicit in the very notion of the opinio juris sive necessitatis…. The frequency, or even habitual character of the acts is not in itself enough.

²⁰⁹ Id. at 43, para. 75.

²¹⁰ Mendelson, supra note 196, at 200. See also Townsend-Gault & Stormont, supra note 17, at 58.

²¹¹ See I. C. MacGibbon, Customary International Law and Acquiescence, 1957 Brit. Y.B. Int’l L. 115, esp. 129–30.

²¹² See Martin Dixon, Textbook on International Law 28 (3d ed. 1996).

²¹³ Nicaragua case, 1986 ICJ Rep. at 98, para. 186. See also Miyoshi, Oiland Gas, supra note 8, at 4; Miyoshi, Basic Concept, supra note 8, at 10.

²¹⁴ See North Sea Cases, 1969 ICJ Rep. at 43, para. 74.

²¹⁵ “The Party which relies on a [regional or local] custom of this kind must prove that this custom is established in such a manner that it has become binding on the other Party.” Asylum Case (Colom./Peru), Judgment, 1950 ICJ Rep. 266, 276 (Nov. 20).

²¹⁶ See Townsend-Gault, supra note 8, at 282.

²¹⁷ Id. at 283.

²¹⁸ See, e.g., the separate opinion of Judge Jessup in the North Sea Cases, 1969 ICJ Rep. at 82, where he notes that the principle of international cooperation is well established under customary international law.

²¹⁹ See Onorato, supra note 30, at 327.

²²⁰ The inclusion of such clauses has become standard practice in European maritime delimitation agreements. The practice of oil-producing states in the Persian Gulf and Southeast Asia is even more significant. Nearly every delimitation agreement concluded since 1969 in these regions provides for cooperation regarding common deposits. See also note 11 supra.

²²¹ See Lagoni, supra note 9, at 235. This observation is echoed by Reid, supra note 37, at 214.

²²² See Onorato, supra note 30, at 330.

²²³ See id. at 330–31. These general principles are acknowledged sources of international law and are applied by the ICJ under Article 38(1) (c) of its Statute, especially in areas where international law is not well established.

²²⁴ William T. Onorato, Joint Development of Sea-bed Hydrocarbon Resources: An Overview of Precedents in the North Sea, 6 Energy 1311, 1312 (1981).

²²⁵ See Lagoni, supra note 9, at 235 (citing well-established precedents such as the Tacna Arica arbitration, 19 AJIL 393,398 (1925); Railway Traffic between Lithuania and Poland, 1931 PCIJ (ser. A/B) No. 42, at 108, 116; Lac Lanoux, 13 R.I.A.A. 281, 285 (1957); and North Sea Cases, 1969 ICJ Rep. at 46, para. 86).

²²⁶ Id. at 238 (citing Railway Traffic between Lithuania and Poland, 1931 PCIJ (ser. A/B) No. 42, at 116; and North Sea Cases, 1969 ICJ Rep. at 48).

²²⁷ See Miyoshi, Bask Concept, supra note 8, at 7.

²²⁸ Id. at 9.

²²⁹ See Willy Østreng, Reaching Agreement on International Exploitation of Ocean Mineral Resources, 10 Energy 555 (1985).

²³⁰ Beginning with the 1974 Japan–South Korea Joint Development Agreement, supra note 20; and followed by the 1979 Memorandum of Understanding between Malaysia and Thailand, in conjunction with the 1990 Agreement on the Constitution of the Malaysia-Thailand Joint Authority, supra note 19; the 1989 Zone of Co-operation Treaty between Indonesia and Australia, supra note 80; and, more recendy, the 1992 Malaysia-Vietnam Memorandum of Understanding, supra note 80.

²³¹ See “Bilateral State Practice in Joint Development,” supra p.787, for brief descriptions of all these agreements.

²³² As reflected in Article 38(1)(b) of the ICJ Statute. See North Sea Cases, 1969 ICJ Rep. at 43, para. 74. Both Lagoni, supra note 9, at 233; and Miyoshi, Basic Concept, supra note 8, at 10, consider this question.

²³³ See Miyoshi, Basic Concept, supra note 8, at 10.

²³⁴ See id.

²³⁵ See id. Miyoshi reiterated this point more recendy in Miyoshi, Oil and Gas, supra note 8, at 4.

²³⁶ Reid, supra note 37, at 215.

²³⁷ Id. at 215–16.

²³⁸ See Lagoni, supra note 16, at 355. See also LOS Convention, supranote 1, Art. 300.

²³⁹ See 1998 ILA Report, supra note 8, at 29, para. 40. The latter part of Article 300 of the LOS Convention also cautions against states’ exercising their rights in a manner that would constitute an abuse of these rights.

²⁴⁰ See id. See also the separate opinion of Judge Jessup in North Sea Cases, 1969 ICJ Rep. at 83.

²⁴¹ See 1 Fox et al., supra note 8, at 38.

²⁴² See Onorato, supra note 30, at 327; Lagoni, supra note 16, at 362; and Miyoshi, Basic Concept, supra note 8, at 10. As Churchill, supra note 38, at 57, also notes, “there is probably a rule of international law which prohibits States from exploiting seabed resources in disputed areas.” Furthermore, Churchill and Ulfstein provide five examples of state practice as evidence of this rule of customary international law. See Robin Churchill & Geir Ulfstein, Marine Management in Disputed Areas: The Case of the Barents Sea 87 (1992).

²⁴³ See Miyoshi, Basic Concept, supranote 8, at 10–11; see also Lagoni, supra note 16, at 366.

²⁴⁴ See Miyoshi, Basic Concept, supra note 8, at 10–11; see also Lagoni, supra note 16, at 366 (quoting the Aegean Sea Continental Shelf case, infra note 245, 1976 ICJ Rep. at 11, para. 32, where the Court invoked Article 41(1) of its Statute, which provides that it has the power to indicate provisional measures to preserve the rights of either party, when “the circumstances of the case disclose the risk of an irreparable prejudice to rights [of either party] in issue in the proceedings”).

²⁴⁵ Aegean Sea Continental Shelf (Greece v. Turk.), Interim Protection, 1976 ICJ Rep. 3 (Order of Sept. 11).

²⁴⁶ See Miyoshi, Basic Concept, supra note 8, at 10–11; and Lagoni, supra note 16, at 366 (citing Aegean Sea Continental Shelf, 1976 ICJ Rep. at 10, para. 30).

²⁴⁷ Lagoni, supra note 16, at 366.

²⁴⁸ LOS Convention, supra note 1, Art. 81.

²⁴⁹ See Lagoni, supra note 9, at 235.

²⁵⁰ See 1988 ILA Report, supra note 8, at 38, para. 52.

²⁵¹ Bundy, supra note 50, at 27, for example, recounts many instances in the Mediterranean (Libya/Malta and Libya/Tunisia), the Middle East and the South China Sea where unilateral drilling, even for exploratory purposes, has been the subject of strenuous protest.

²⁵² Gault, supra note 53, at 302. See id. for examples of good oil-field practice. See also, e.g., the Argentina-UK Joint Declaration, supra note 139, para. 2 (providing for the exploration and exploitation of hydrocarbons within the areas of special cooperation in the southwest Atlantic to be undertaken in accordance with good oil-field practice, drawing from the two Governments’ experiences in the southwest Adantic and the North Sea, where transboundary unitization agreements are well established).

²⁵³ Compare Lagoni, supra note 9, at 243, who suggests that states are compelled by only practical, as opposed to legal, reasons to cooperate.

²⁵⁴ Id. at 242–43.

²⁵⁵ Under the principles laid down in the Trail Smelter arbitration (U.S. v. Can.), 3 R.I.A.A. 1905 (1941); and the Corfu Channel case (UK v. Alb.) (Merits), 1949 ICJ Rep. 4, 22 (Apr. 9).

²⁵⁶ See 1 Fox et al., supra note 8, at 33.

²⁵⁷ See Onorato, supra note 30, at 328.

²⁵⁸ See id. at 329–30.

²⁵⁹ See Miyoshi, Oil and Gas, supra note 8, at 5; see also Miyoshi, Basic Concept, supra note 8, at 14.

²⁶⁰ Lagoni, supra note 9, at 238 n.115, 239.

⁸⁶¹ See Miyoshi, Baste Concept, supra note 8, at 13–14; see also Lagoni, supra note 9, at 217; and Gault, supra note 53, at 302–03.

²⁶² In line with LOS Convention, supra note 1, Art. 83(1), on delimitation of the continental shelf.

²⁶³ Either as a result of such delimitation negotiations, or as provisional arrangements pending a final delimitation agreement, provided for in Articles 74(3) and 83(3) of the LOS Convention, respectively.

²⁶⁴ LOS Convention, supra note 1, Art. 142 (2).

²⁶⁵ Here it is pertinent to note that the prior consent requirement also accords with developments in public international law governing environmentally hazardous activities that may damage other states’ interests, such as the transboundary movements of hazardous wastes, where the prior informed consent of both importing and transit states is necessary before shipments are permitted. See Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and Their Disposal, Mar. 22, 1989, Arts. 4, 6, 28 ILM 657 (1989). Article 7 provides that the prior informed consent requirement shall also apply to nonparties.

²⁶⁶ See Miyoshi, Basic Concept, supra note 8, at 14.

²⁶⁷ Aegean Sea Continental Shelf (Greece v. Turk.) (Interim Protection), 1976 ICJ Rep. 3, 10, para. 30 (Order of Sept. 11).

²⁶⁸ Lagoni, supra note 16, at 364.

²⁶⁹ Id.

²⁷⁰ See Miyoshi, Basic Concept, supra note 8, at 14 n.65 (citing an improvised memorandum contributed by Lagoni to the Third Workshop, supra note 51). This point is arguably made in furtherance of die principle of effectiveness under international law, by which states must be allowed to exercise their lawful rights effectively and without undue interference.

²⁷¹ See Miyoshi, Basic Concept, supra note 8, at 14.

²⁷² Id.

²⁷³ Lagoni, supra note 16, at 367.

²⁷⁴ See Onorato, supra note 30, at 331.

²⁷⁵ See id. (citing Barcelona Traction, Light & Power Co. (Belg. v. Spain) (Second Phase), 1970 ICJ Rep. 3, 33, para. 38, and esp. 37, para. 50 (Feb. 5)).

²⁷⁶ Ian Brownlie, Legal Status of Natural Resources in International Law (Some Aspects), 162 Recueil des Cours 245, 289(1979 I).

²⁷⁷ See Reid, supra note 37, at 221.

²⁷⁸ See, e.g., Zhiguo Gao, Legal Aspects of Joint Development in International Law, in Sustainable Development and Preservation of the Oceans: The Challenges of Unclos and Agenda 21, at 629, 642 (Mochtar Kusuma-Atmadja et al. eds., 1997).

²⁷⁹ See Lagoni, supra note 16, at 366 (citing Aegean Sea Continental Shelf, 1976 ICJ Rep. at 10–11, paras. 30–33).

²⁸⁰ Significantly, certain transboundary deposit clauses provide for stricter or more specific resolution methods than others. See Ong, supra note 91, at 83–85.

²⁸¹ For example, Agreement establishing certain sea-bed boundaries in the area of the Timor and Arafura Seas, May 18, 1971, Austl.-Indon., Art. 7, Legislation and Treaties, supra note 139, UN Doc. ST/LEG/SER.B/18, at 433, 10 ILM 830 (1971); and Supplementary Agreement, Oct. 9, 1972, Austl.-Indon., Art. 7, UN Doc. ST/LEG/SER.B/18, supra, at 441.

²⁸² Even if such an arrangement only involves the payment of adequate compensation for the right to exploit the deposit unilaterally.

²⁸³ See Lagoni, supra note 16, at 367.

²⁸⁴ See Onorato, supra note 30, at 330.

²⁸⁵ North Sea Cases, 1969 ICJ Rep. at 43, para. 74.