In May 1988 , a US mediation team &ndash; headed by Chester A. Crocker , US Assistant Secretary of State for African Affairs &ndash; brought negotiators from Angola , Cuba , and South Africa , and observers from the Soviet Union together in London . Intense diplomatic activity characterized the next 7 months , as the parties worked out agreements to bring peace to the region and make possible the implementation of UN Security Council Resolution 435 ( UNSCR 435 ) . At the Ronald Reagan/Mikhail Gorbachev summit in Moscow ( 29 May – 1 June 1988 ) between leaders of the United States and the Soviet Union , it was decided that Cuban troops would be withdrawn from Angola , and Soviet military aid would cease , as soon as South Africa withdrew from Namibia . Agreements to give effect to these decisions were drawn up for signature in New York in December 1988 . Cuba , South Africa , and the People 's Republic of Angola agreed to a complete withdrawal of foreign troops from Angola . This agreement , known as the '' Brazzaville Protocol '' , established a Joint Monitoring Commission ( JMC ) with the United States and the Soviet Union as observers . The Tripartite Accord , comprising a bilateral agreement between Cuba and Angola , and a tripartite agreement between Angola , Cuba and South Africa whereby South Africa agreed to hand control of Namibia to the United Nations , were signed at UN headquarters in New York City on 22 December 1988 . ( UN Commissioner N ° 4 Bernt Carlsson was not present at the signing ceremony . He was killed on flight Pan Am 103 which exploded over Lockerbie , Scotland on 21 December 1988 '' en route '' from London to New York . South African foreign minister , Pik Botha , and an official delegation of 22 had a lucky escape . Their booking on Pan Am 103 was cancelled at the last minute and Pik Botha , together with a smaller delegation , caught the earlier Pan Am 101 flight to New York . ) Within a month of the signing of the New York Accords , South African president P. W. Botha suffered a mild stroke , which prevented him from attending a meeting with Namibian leaders on 20 January 1989 . His place was taken by acting president J. Christiaan Heunis . Botha had fully recuperated by 1 April 1989 when implementation of UNSCR 435 officially started and the South African – appointed Administrator-General , Louis Pienaar , began the territory 's transition to independence . Former UN Commissioner N ° 2 and now UN Special Representative Martti Ahtisaari arrived in Windhoek in April 1989 to head the UN Transition Assistance Group 's ( UNTAG ) mission
flight Pan Am 103
Pan Am Flight 103
History of Namibia