Johannesburg - The mudslinging between Deputy President Jacob Zuma and National Director of Public Prosecutions (NDPP) Bulelani Ngcuka resembled a soap opera, the New National Party said yesterday.

Party spokesman Carol Johnson said in a statement that both parties should "keep quiet" and allow the judicial commission to be headed by Judge Joos Hefer to do its job of investigating allegations that Ngcuka had been an apartheid spy.

"The latest skirmish between ... Zuma and ... Ngcuka is detracting from the investigation being done by the Hefer Commission," she said.

The party was reacting to a statement by Zuma on Monday accusing Ngcuka of abusing his power and authority when he had a "secret meeting" with black editors in July to discuss cases being investigated by the elite unit, Scorpions.

"This type of mudslinging between these two prominent figures is starting to look like a soap opera.

"The time has come for both parties to keep quiet and let the Hefer Commission do its job. These accusations and counter-accusations are doing both their offices an injustice," Johnson said.

On Monday Ngcuka also challenged Zuma to present the commission with evidence that he was abusing his power.

"If Mr Zuma has any evidence of abuse and of ulterior motive, he is challenged to present such evidence to the commission of inquiry established by the president for this purpose," said acting NDPP spokesman Rudolf Mastenbroek.

"Moreover, if he feels that his character has been impugned by anything done or said by the NDPP or the National Prosecuting Authority, he is challenged to exercise his legal rights as accorded under our constitutional democracy, and to institute defamation proceedings in a court of law."

The allegations that Ngcuka had been a spy for the previous government surfaced after Zuma was investigated for alleged corruption linked to the country's multi-billion rand arms deal and then declined to prosecute the deputy president.

With acknowledgements to Sapa and the Cape Times.