We consider a two-period model of an indebted developing country endowed with a natural resource whose extraction causes negative global externalities, where the country may borrow in period one and there is asymmetric information about its willingness to service its loans. We show that when the resource is large, the interest rate on new borrowing equals the resource growth rate. A greater initial debt level then leads to reduced new borrowing and more rapid extraction. An outside 'donor' may affect the resource extraction of the country. Donor schemes that tie debt reduction to postponing or abstaining from extraction of the resource are more powerful than non-conditional schemes in reducing the extraction rate for governments that actually repay, but may in some cases lead to a greater probability of default through increased debt. While conditional schemes generally are potentially Pareto-superior to non-conditional ones, the welfare of the borrowing country is higher with non-conditional schemes.