South Africa's 32 Roman Catholic bishops issued a statement here today calling for selective economic pressure on South Africa that would not increase black unemployment nor destroy the country's economic infrastructure.

The church's statement adds to the growth of moral support in South Africa for economic pressure to try to force the Pretoria government to dismantle apartheid and end white minority rule.

Meanwhile, Winnie Mandela, wife of imprisoned black nationalist leader Nelson Mandela, denied that she was an advocate of violence and said recent reports implying she had approved of the killing of black "collaborators" were inaccurate.

The statement by the Catholic bishops appeared to seek a compromise at the end of a three-day conference at which the bishops reportedly were divided on sanctions.

Noel Bruyns, press officer for the bishops, said they had drawn a distinction between "disinvestment," which involves companies being closed down with a consequent loss of jobs, and "divestment," which involves foreign investors selling their South African shareholdings so that they withdraw but the factories continue to operate.

"The bishops felt divestment was an appropriate form of economic pressure but they were opposed to disinvestment," Bruyns said.

The Roman Catholic Church is the second largest Christian faith in South Africa after the Dutch Reformed Church, to which most government-supporting Afrikaners belong. It has the largest following among blacks.

Winnie Mandela clarified her stand on violence in a speech to a May Day rally in Soweto yesterday.

She said she had been misunderstood and reported out of context three weeks ago when news agencies gave the impression she had condoned, in an impromptu speech, the execution of blacks who collaborated with the apartheid system.

The agencies quoted Mandela as saying on a townships tour that "together, hand in hand, with our boxes of matches and our necklaces, we shall liberate this country."

This was taken to signify approval of the so-called "necklace" executions of a number of black "collaborators," who have been burned to death with a blazing tire filled with gasoline around their bodies.

Mandela said her words were not intended to condone the killings, but in the context in which they were uttered made the point that blacks could not fight against the military might of the Pretoria regime with matches and necklaces.

"What I said was that the Pretoria regime has declared war on the people of this country, and the time will come when you will have to defend yourselves not with matches and necklaces but with the same might that is being unleashed against you," Mandela said.