South Africa, Cuba and Angola pledged peace in Southwestern Africa Tuesday, opening the way for withdrawal of 50,000 Cuban troops from Angola and independence for the continent's last colony of Namibia.

U.S. Assistant Secretary of State Chester Crocker, who led eight months of intermittent negotiations on three continents, said the accord is "a new symbol of peace in the world." It ends years of negotiating over one of Africa's most intractable disputes.Officials of the three countries signed the agreement, to be finalized in New York on Dec. 22, at a ceremony attended by Crocker, host President Denis Sassou-Nguesso of Congo, and Soviet and United Nations' representatives.

"We want to be accepted by our African brothers. We need each other," South African Foreign Minister R.F. Botha declared after he signed for the white-led country. "A new era has begun. We are removing race discrimination," he said.

Ricardo Alarcon, Cuban vice minister for foreign affairs, and Angolan armed forces chief Gen. Antonio dos Santos Ndalu signed for their governments.

Botha earlier told reporters the U.N.-supervised independence process for South West Africa, which is better known as Namibia, will begin April 1. Elections will be held seven months later and the mineral-rich territory will be independent in about a year, he said.

Mediated by the United States and supported by the Soviet Union, the agreement will free the former German colony from 73 years of South African control and end 22 years of sporadic bush warfare.

"This will bring an end to international conflict in Southwestern Africa," Crocker said. "It is the end of a sad chapter in African history."

Still unsettled is the civil war in Angola between the pro-Soviet government and rebels backed by South Africa and the United States. But the treaty will bar the involvement of South African and Cuban forces in that arena, scaling down its potential for regional conflict.