Angola tonight called for an urgent meeting of the United Nations Security Council to demand "the immediate and unconditional withdrawal" of South African forces from southern Angola.

The announcement, made ina late-night Radio Angola broadcast, came after the Foreign Ministry said the military situation had deteriorated in the south where South African and Angolan forces are clashing.

Angola still gave no details of casualties, although South Africa said eight of its troops and 29 guerrillas of the South-West Africa Peoples Organization, had been killed.

This Mediterranean-style capital about 750 miles away from the fighting remained calm, despite the reports of the clash and the government's order for a general military mobilzation.

No special police or military measures were evident in Luanda, where most Angolans seemed preoccupied by the second Central African games taking place here. The government is using the two-week, 11-nation games as an event to promote national pride and unity, and most workers are being given afternoons off to attend the sporting events.

Despite President Jose Eduardo dos Santos' hint that he might call on the 15,000 to 20,000 Cuban troops in the country to fight the South Africans, there was no outward change in the placid atmosphere at the Cuban Embassy.

Cunan Charge d'Affaires Huberto Reynaldo Calbia was home this morning taking care of a household problem. Ambassador Rafael Francia Mestre is on leave in Havana and there are no plans to speed up his return.

First Secretary Felix Wilson said he knew of no special contacts between the embassy and the Angolan government.

President dos Santos sent a message protesting the South African actions to Fidel Castro but in his role as leader of the nonaligned group of nations, not as Cuban president. Kenyan President Daniel arap Moi, chairman of the Organization of African Unity, also received a message.

The Foreign Ministry called in the envoys of France, Britian and West Germany, and the government radio gave prominence to criticism of the South African actions by the latter two countries, Portugal and the Soviet Union.

The government in the past has pointed out the lack of Western condemnation of South African attacks.