Citing the political situation in South Africa, an ad hoc committee of Columbia University's Board of Trustees has recommended selling the university's $39 million worth of stock in companies operating in South Africa.

The recommendation, set for action by the governing board Oct. 7, marks a significant symbolic step in the nationwide campus divestiture drive. That is likely to be revived as students return to colleges amid continuing racial violence and tough responses by the South African government.

Columbia trustees have repeatedly resisted student calls for total divestiture. These culminated in a 1960s-style barricade of an administration building last spring.

On July 17, the trustees rejected total divestiture, condemning apartheid but only selectively divesting from American companies that have not signed the Sullivan principles, voluntary agreements by businesses operating there to employ and promote nonwhites.

The committee decision on total divestiture was reached Tuesday and released Wednesday. A university official said the crisis in South Africa has had more impact on trustees than did campus blockades.

"After raising hopes for significant reforms in the apartheid structure, the South African government has dashed them," university spokesman Fred Knubel said. "It has moved ruthlessly to buttress the existing system . . . ."

The six-member committee's previous votes have been accepted by the 24-member board.