Confronted with a number of boundary conflicts and interstate civil uprisings, OUA has been instrumental in settling, or at least influencing the amicable settlement of such disputes, some of which had threatened the very existence of the Organization (among these are the Nigerian Civil War, the Angolan Civil War, disputes between Guinea and Senegal and Côte d'Ivoire, Uganda-Tanzania conflict, border disputes between Somalia and Ethiopia, and between Sudan and Ethiopia). A particularly difficult crisis has been faced since 1982 over the recognition of the Sahrawi Arab Democratic Republic (SADR). OAU plays a role in defending the independence of nations whose sovereignty and territorial integrity are threatened (among member nations which have received such assistance are the Congo, Nigeria - where a Civil War flared up and threatened the Federal Republic of Nigeria to its very foundations, Egypt – which was aggressed and occupied in parts by Israeli forces in 1967, and Guinea). The Summit of 1993, Cairo, established the OAU Mechanism for Conflict Prevention, Management and Resolution.