Black activists have refused to cooperate with an inquiry into Britain's worst racial riots in years, but postponed a march through the Brixton district that police feared would touch off more violence.

Rudy Narayan, a Guyanese-born lawyer heading the fledgling Brixton Defense Committee, told reporters last night that the committee voted unanmiously against "support of any kind" for the government inquiry into the rioting.

However, those at the meeting, closed to whites and reporters, voted to postponed a decision on holding a rally, which had been planned for Sunday, saying it first wanted to consult those arrested in the four nights of street battles that began last Friday.

Narayan said some outsiers were more axious than local people to hold a march. "We are not willing to be used by people from outside the community," he said.

Other black leaders who attended the meeting, and refused to be identified, said the inquiry under Lord Scarman should be expanded to include underlying social and economic conditions in Brixton.

Police and some community leaders had expressed concern that the call for a rally by the committee, which is demanding amnesy for 224 people arrested in the riots, would increase tension in the area.