The ANC has tightened the screws on Justice Minister Penuell Maduna, saying he was "hurting", and effectively accusing him of lying.

Following the party's scathing attack on Maduna earlier this week, ANC secretary-general Kgalema Motlanthe on Wednesday implied that Maduna had lied when he said he had told President Thabo Mbeki of his decision to quit after next year's general election.

The party launched a scathing attack on Maduna earlier this week after he told Independent Newspapers he would be standing down at the end of his term of office because of the storm around him amid allegations that he was a spy for the apartheid government.

"I told the president that my family are saying I should resign because they can't take it any longer," Maduna said.

On Maduna's comments that "the ANC is hurting badly" in the wake of the apparent in-fighting over the way he and Bulelani Ngcuka, the National Director of Public Prosecutions, had handled the corruption investigation into Deputy President Jacob Zuma, Motlanthe suggested that Maduna was taking strain.

"He is a member of the ANC. If he is hurting then obviously the ANC is hurting ... that's something that no one can refute. But there's certainly no division in the ANC," Motlanthe said.

Maduna's shock announcement last weekend came just days after Mbeki had broadened the Hefer Commission's terms of reference to include a probe into whether Maduna had abused his office and whether he was a spy.

Zuma has been engaged in a tense standoff with Maduna, accusing the justice minister of helping Ngcuka to drag his name through the mud.

Maduna sat alongside Ngcuka at a press conference where the latter said that while there was a prima facie case of corruption against the deputy president, he would not prosecute because the case was not "winnable" - effectively denying Zuma the opportunity to defend himself in court.

With acknowledgements to Jeremy Michaels and The Star.