JOHANNESBURG, JAN. 12 -- The head of the London-based South African Non-Racial Olympic Committee said here today it is "highly improbable" South Africa would make enough progress in integrating its still mostly racially segregated sports to warrant admission to the 1992 Olympic Games.

Speaking to reporters after a daylong meeting with officials from four other South African sports federations, Sam Ramsamy appeared anxious to scotch hopes among whites here for South Africa's early return to international sports.

"We didn't talk about participation," Ramsamy said. "What we talked about was nonparticipation. We all felt very strongly and we all agreed that at this particular stage South Africa's participation internationally is not on."

South Africa was expelled from the Olympic movement in 1970 because of its apartheid policies. White sports fans have been full of hope since President Frederik W. de Klerk began scrapping apartheid legislation and ending bans against black political groups last February that their country might be acceptable now for readmission.

But Ramsamy made it clear during a news conference that South Africa's sports federations, divided both along racial and intra-black factional lines, still had a lot of work to do to "put our house in order."

At an earlier news conference, Tommy Sithole of the Association of National Olympic Committees of Africa (ANOCA), read a letter from Jean Claude Ganga, the organization's president, telling South Africans that their primary goal should be "to unite and form a single nonracial sports organization."

Ganga said ANOCA had decided to open "a new chapter" in its relations with South Africa in light of de Klerk's reforms and to help it gain "limited recognition" by African and international sports bodies as "a first step toward respectability."

ANOCA has agreed to set up a 10-man committee, including two ANOCA representatives plus two from each of the four federations operating inside South Africa to promote and monitor sports integration and unity here.

The International Olympic Committee is sending its own delegation here, probably in April, to assess the situation and could conceivably decide to readmit South Africa to the movement by 1992. But it is unlikely to overrule the assessment of the African Olympic committees as to whether and when the country has made enough progrees to warrant readmission.

Ramsamy, the exiled South African executive chairman of the London-based SANROC, is also chairman of the newly formed, 10-man interfederation sporting panel.

He said that a top priority of the new committee is applying pressure to those South African groups still sponsoring foreign teams' play here to stop such activities.