Government has moved to dampen the political furore raging around the arms-deal probe by appointing a judicial commission of inquiry to probe claims that prosecutions chief Bulelani Ngcuka was an apartheid spy.

The work of the commission, which will be headed by a yet-to-be-named retired judge, is due to be completed within weeks in the hope of limiting any damage being done to the work of the crimefighting Scorpions unit, which Ngcuka also heads.

The move was seen yesterday as a bid by President Thabo Mbeki to take the political heat out of the row between his deputy, Jacob Zuma, and Ngcuka. This has been escalating since Ngcuka claimed to have a prim facie case of corruption against Zuma, but decided not to prosecute him.

It is alleged Zuma solicited a bribe from an arms deal bidder.

Mbeki has come under pressure to intervene in the row, but has repeatedly said the legal process should take its course. The appointment of a judicial inquiry, which is independent of government, would enable the president to be seen to be adopting an even-handed approach.

The decision was greeted with delight by Ngcuka's spokesman, Sipho Ngwema, who said it would give Ngcuka the opportunity to prove he never colluded with the apartheid regime.

Government spokesman Joel Netshitenzhe said that in deciding on the way forward government took into account that the issue "was already under debate amongst the public relating to a head of a unit dealing with many sensitive matters".

"In order to ensure this matter is brought to rest, it was necessary to very, very urgently ensure that a commission is established so it could determine what the truth of the matter is," Netshitenzhe said. Government was confident the allegations did not emanate from any of its intelligence agencies.

Mbeki's even-handed approach was evident in Parliament yesterday, when he expressed confidence in both Zuma and Ngcuka. Mbeki said government would not reorganise itself on the basis of mere allegations. He was responding to a question from Democratic Alliance leader Tony Leon, who asked if he would ask Zuma to step down until the matter had been resolved.

Mbeki said he agreed with Leon that Zuma was facing serious allegations, but disagreed that public representatives should resign or be suspended on the basis of mere allegations.

He also criticised the DA for choosing to believe Ngcuka when he said he had a prima facie case against Zuma, but disbelieving him when he said there was not enough evidence to charge him.

Mbeki said no-one in SA had any evidence to show corruption had taken place in the arms deal. Those claiming the opposite had political agendas. Mbeki said he had absolute confidence that Ngcuka was discharging his duties in terms of the law.

With acknowledgements to Robyn Chalmers, Wyndham Hartley and the Business Day.