Deputy President Jacob Zuma - who is reportedly under investigation for alleged corruption - will continue to lead the moral regeneration campaign, according to President Thabo Mbeki.

He was replying in writing to a parliamentary question from Democratic Alliance MP Raenette Taljaard.

In her reaction, Taljaard told Sapa on Tuesday that the president continued to deal with a deputy that was under a cloud of suspicion and yet was allowed to lead the country's moral regeneration campaign.

"If that is the type of moral leadership, we will not be surprised if the number of Yengenis multiply, because they're getting their answer from the president."

Zuma has repeatedly claimed his innocence after allegations that he tried to solicit a half-a-million rand bribe from the former Southern African head of Thomson-CFS, Alain Thetard.

The DA last year asked the president to appoint a commission of inquiry to probe the allegations against Zuma.

Taljaard received a letter from a presidential adviser dated December 6 stating that commissions of inquiry were not appointed on the basis of mere allegations.

Asked whether this was presidential policy, Mbeki replied on Tuesday: "Yes. Commissions of inquiry cost money. They must therefore be appointed on the basis of clear evidence presented to the president, backed by some material facts.

"The possibility of using other state agencies to conduct inquiries must also be considered."

Asked whether this was consistent with his decision to appoint a commission of inquiry into the depreciation of the rand after allegations by then Sacob CEO Kevin Wakeford, the president replied: "Yes. In the case referred to, allegations were supported by evidence."

According to newspaper reports, Zuma is under investigation by the Scorpions, although Justice Minister Penuell Maduna last month told reporters he did not know whether this was the case.

"I know as much as the media have reported," he said then.

Maduna - who is the politically accountable head of the Scorpions - added: "I am therefore not in the position to say whether there is a probe into the deputy president, or, if there is one, when that will be concluded. I don't know."

With acknowledgements to Sapa, Angela Quintal and www.iafrica.co.za