In their first meeting since a South African commando unit reportedly tried to sabotage a Gulf Oil refinery in Angola's Cabinda Province May 21, Foreign Minister Roelof F. (Pik) Botha assured U.S. Ambassador Herman Nickel today that his country would not attack American installations or personnel anywhere in the world.

In a statement issued after the meeting, Botha said he also told the ambassador that, despite Angolan indications that it had broken off negotiations with Pretoria because of the Cabinda raid, South Africa was still committed to seeking a Namibian settlement on the basis of U.N. Security Council Resolution 435, provided agreement could be reached on the withdrawal of Cuban troops from Angola.

Both assurances were seen as an attempt to mollify the Reagan administration, which has been embarrassed and angered by the Cabinda raid.

South Africa continues to deny that its commandos were intercepted while attempting to sabotage the refinery, despite corroboration of Angola's charge by the captured commander of the unit, Capt. Wynand du Toit, at a press conference in Luanda, Angola, last week.

Pretoria says that the commandos were gathering intelligence data about guerrilla bases in northern Angola.

Last week Botha said he had been informed through U.S. channels that Angola had broken off negotiations for a regional peace settlement, and he questioned whether meaningful discussions on Namibian independence were still possible.