The African National Congress spy saga, which has divided the party, was taken to a new level this week with the intervention of President Thabo Mbeki who warned that the rank-and-file of the ANC would not forgive those who levelled charges at ANC members for being apartheid agents.

Mbeki's remarks, the first since allegations that Bulelani Ngcuka, the national director of prosecutions, was an apartheid spy were made last month, came a week ahead of a judicial commission of inquiry to probe the spy claims.

ANC veteran Mac Maharaj, who has indicated he will testify at the commission, has supported the claims.

Writing in his weekly letter on the ANC Today website, much of Mbeki's pre-emptive attack on those demanding that the ANC publish its spy lists appeared to be directed at Patricia de Lille, the Independent Democrats leader, who first claimed in parliament in 1997 that she had a list of alleged senior ANC members who had spied for the apartheid regime.

But one section of Mbeki's intervention on the spies issue appeared to be directed at those within ANC ranks who have made allegations that Ngcuka was an apartheid spy.

Ngcuka and his family and associates have flatly denied the allegations.

"In time, all those who feel free to charge others in our ranks with having been agents of apartheid, will have to answer for the charges they have made," Mbeki said. "The masses of our people will not forgive them for what they are trying to do, to undermine our country's movement forward, towards the genuine emancipation of the ordinary working people of our country."

Mbeki said that the issue of who was a spy in the apartheid era was irrelevant in present-day South Africa and to make such allegations amounted to an attempt to undermine the efforts to achieve national reconciliation.

"When we took the decision to achieve reconciliation rather than retribution, and thus established the truth and reconciliation commission, we decided to forgive all those who might have caused unjustified harm to anyone in our country and elsewhere, in pursuit of the objectives either to perpetuate apartheid, or to achieve the liberation of the oppressed," he said.

"And yet, today, there are some in our country who are acting in a manner that seeks to destroy this effort at national reconciliation."

Mbeki said there were no authentic lists of apartheid spies.

"Those who claim that such a list exists are telling an outright lie."

Frene Ginwala, the speaker of parliament, said in a telephonic interview from India that those who were making allegations of spying should have disclosed such information earlier.

"Anyone in the ANC who had evidence that the national director of public prosecutions was a spy should have raised it within the ANC," she said. "It should have been raised when crucial appointments were made."

She questioned the relevance of determining whether ANC officials had been former apartheid spies.

"I would like to pose a question to the media: if Bulelani Ngcuka was an agent then what would be the relevance of that?"

Maharaj declined to comment on Mbeki's remarks but said he had made it clear he would testify at the commission which is due to start its hearings a week from Monday.

De Lille said that it was "reactionary" and selective of Mbeki to appoint a commission to deal with the allegations and then talk outside the commission about a matter which was beyond the commission's terms of reference.

"Then why did the government establish a commission to look into allegations made by Maharaj who is an ANC member?" De Lille asked.

With acknowledgements to John Battersby and the Sunday Independent.