The Greentree Agreement is a formal treaty which resolved the Cameroon–Nigeria border dispute over the oil and natural gas-rich Bakassi peninsula. The dispute had roots as far back as 1913; in 1981, 1994, and 1996 armed clashes between Nigeria and Cameroon took place in Bakassi. The dispute was referred to the International Court of Justice and on 10 October 2002 the ICJ ruled in favor of Cameroon.