Sovereign immunity — Absolute and restrictive theories — Which theory applicable to actions in personam in England — Extent of restrictive theory — Whether permitting inquiry into meaning and effect of foreign State’s legislation in case to which that State is a party — Act of State doctrine

International law in general — Relation to municipal law — Whether customary international law part of the law of England — Whether doctrine of binding precedent applicable to decisions on international law — Irreconcilable decisions of Court of Appeal — The law of England