Top ANC leaders on either side of the spy allegations divide are preparing to slug it out before a former apartheid-era judge.

The stage is set for a high-profile battle between two major camps dividing the ANC on whether Bulelani Ngcuka, the head of the National Prosecuting Authority (NPA), was an apartheid-government spy.

Retired chief justice Joos Hefer's commission of inquiry, appointed by President Thabo Mbeki, is set to begin in earnest in Bloemfontein on Thursday with representations and written submissions, according to commission spokesperson John Bacon.

Those set to appear before Hefer include Deputy President Jacob Zuma, Mo Shaik - the brother of Schabir, Zuma's financial adviser - and former transport minister Mac Maharaj. The commission was able to get hold of Independent Democrats leader Patricia de Lille only yesterday, and she will soon be served with a subpoena.

Justice Department spokesperson Kaiser Kganyago said his minister, Penuell Maduna, had expressed his willingness to present himself before the commission if asked to do so.

"He has made an undertaking to co-operate fully with the commission," Kganyago said.

Bacon said the commission had written to the National Intelligence Agency (NIA) requesting information that could be relevant to the work being done by the commission.

While Zuma had previously said he would be willing to testify - if such a request were made to him - his spokesperson, Zanele Mngadi, did not want to comment about the matter yesterday.

The commission is a sequel to claims that Ngcuka was allegedly abusing his office to investigate people who had allegedly investigated him, on suspicion by the ANC, that he was an informer of the apartheid regime under Project Bible.

Ngcuka's accusers claimed he was registered with the regime as agent RS452, which later turned out to be a white woman living in the Eastern Cape. The commission is tasked with unearthing the truth on whether he is indeed agent RS452 or was registered in any other name or had collaborated with the apartheid government in any other way.

Sipho Ngwema, Ngcuka's spokesperson, said that "from our side it's all systems go". He said Ngcuka "could hardly wait" for the commission to start and finish its job so that the NPA could focus on its core business.

Lorna Daniels, spokeswoman for the NIA, could not be reached for comment.

Bacon said Ngcuka, through his lawyer Dumisani Tabata and advocate Marumo Moerane SC, had made an undertaking to provide the commission with all the relevant facts and, where necessary, evidence to substantiate their positions.

He added that despite an open invitation for members of the public to voluntarily provide information relating to the commission's work, the response had been poor. The only people who had volunteered to help were Maharaj and Mo Shaik, Ngcuka's principal accusers.

Bacon said the commission had also made contact with mining magnate Brett Kebble, who recently made various allegations against Maduna and Ngcuka.

First to appear on Thursday will be senior journalist Raymond Louw, who will make a voluntary public submission on behalf of the South African National Editors' Forum's media freedom subcommittee.

Louw said he would state why a journalist should not have to give evidence before a commission.

Bacon said other journalists asked to testify include Sunday Times editor Mathatha Tsedu, who refused to print an article in which the spying allegations against Ngcuka were made.

The editor of City Press (which did run the article), Vusi Mona, and one of his journalists, Elias Maluleke, are also in the line-up of witnesses.

"We are still in the beginning phases of our investigation," Bacon said. "We have made contact with the police service and security branches (to establish whether Ngcuka was an informer)."

With acknowledgements to Makhudu Sefara, Christelle Terreblanche and The Star.