SOWETO, South Africa -- The African National Congress threatened yesterday to walk out of negotiations with the South African government unless the government releases all political prisoners and allows all exiles to return to the country by April 30.
The ANC said the government must also repeal "all repressive legislation" and end all political trials by that date.
Ending its historic conference, the first inside South Africa since the organization was banned 30 years ago, the ANC also threatened to resume its military campaign against the government unless South African authorities stop the violence that has rocked black townships.
The anti-apartheid group agreed to suspend its "armed struggle" on Aug. 6 to improve the climate for negotiations, which are supposed to result in a new constitution giving blacks and whites equal rights.
But since that time, hundreds of blacks have been killed in township violence, which ANC supporters blame on government security forces. They charge that the violence is being orchestrated by whites and is aimed at destabilizing the townships and crushing the anti-apartheid movement.
"We are very concerned at the failure of the government to implement agreements," said Thabo Mbeki, head of the ANC's international affairs department. "We are very concerned at the level of violence in the country."
Speaking at the closing session of the three-day meeting, Nelson Mandela said conference delegates had criticized the group's leaders for suspending the military campaign and on a number of other issues.
But, he added, "there are certain arguments which have been advanced here which we totally reject. The overwhelming majority of our people support negotiations between the ANC and the government."
In the end, the conference passed a resolution calling on ANC leaders to proceed with preliminary talks with the government, which are designed to set the stage for multiparty negotiations on a new constitution.
The conference also passed a resolution supporting the leaders' decision to suspend the armed struggle, but delegates made it clear that the ANC could change its position if the government does not meet its demands.
The ANC conference was the first opportunity that leaders of the anti- apartheid organization have had to consult with their broad membership on the fast-changing political developments in the country since last February, when bans were lifted from the ANC and other groups and the government embarked on a process of reform.
Mr. Mandela said the group was stronger because of the "frank criticism" expressed by members. "We are leaving this hallway closer to one another than we were before," he said.
Many of the 1,600 delegates, including longtime ANC President Oliver Tambo, returned to South Africa for the first time in decades to attend the conference.
The delegates resolved to continue with the ANC's campaign of mass demonstrations and protests during the talks and to maintain their position against lifting international sanctions against South Africa.
Mr. Mbeki said the ANC would talk to the U.S. government and to governments of the European Community, which voted Saturday to lift a ban on new investments in South Africa but to maintain other sanctions.
After the conference, ANC leaders spoke at a rally of more than 50,000 people, who cheered enthusiastically at the suggestion that the armed struggle might be resumed if the government does not cooperate.