South African Foreign Minister Pik Botha pledged his country's full support yesterday for Prime Minister Ian Smith's efforts to negotiate a settlement in Rhodesia snubbing the joint Anglo-American peace initiative.

Botha said outsiders must not be allowed to dictate solutions for Rhodesia. He flew here yesterday to confer with Smith.

Smith said afterward that he was "satisfied that I have the full backing and . . . trust of the South African government." He said the meeting was not linked to the Rhodesian elections set for Aug. 31. Observers felt, however, that South Africa was showing its support for Smith to head off the possibility of a victory by his right-wing opponents.

Smith accused those right-wing opponents of stirring up a controversy over allowing blacks to live in a white Salisbury suburb as a pre-election ploy.

"I am concerned, whether there is an election or not," he said. "Anything which stirs up racial animosity in Rhodesia is contrary to what we are trying to achieve."

It was Smith's first public comment on moves to evict non-whites from an area designated "European" under Rhodesia's Land-Tenure Act. He said the move had been instigated by his political foes.

In Soweto, the black township outside Johannesburg, meantime, violence erupted between police and young blacks for the fourth straight day.

Police opened fire on a group of youths who were throwing rocks, but there were no reports of injuries.