JOHANNESBURG - THABO Mbeki will resign as South Africa's president, his spokesman said on Saturday, after the governing African National Congress told him to stand down in the interests of ANC unity.

'The president has obliged and will step down,' presidential spokesman Mukoni Ratshitanga told 702 Talk Radio in Johannesburg, within hours of the ANC national executive committee's call for him to go.

Mr Mbeki, 66, who succeeded Nelson Mandela as president in June 1999, has been under fire over allegations that he was influential in pressing corruption charges against ANC leader and political rival Jacob Zuma.

'The ANC has decided to recall the president of the republic before his mandate has expired,' the ANC's secretary general Gwede Mantashe told journalists after a meeting of the party leadership.

'Our decision has been concluded, the formalities are now subject to the parliamentary process,' Mr Mantashe said, adding that Mr Mbeki 'didn't express shock, he welcomed the news.

'We have communicated our decision (to Mr Mbeki) and that we will be going through parliamentary process. He has agreed to participate in that process.'

702 Talk Radio said Mr Mbeki - a key player in mediating an end to the political crisis in Zimbabwe - had called a meeting of his government for Sunday to decide the way forward.

Mr Zuma, who ousted Mr Mbeki as head of the ANC last year, is the favourite to succeed him as president.

Mr Mantashe said the decision to ask him to stand down was taken in the interests of party unity.

'This is not a punishment,' he said. 'We decided to take this decision in an effort to heal and reunite the ANC.'

Under the South African constitution, the president is appointed by parliament, which has been dominated by the ANC since the end of apartheid and the start of majority rule in May 1994.

Senior ANC officials had gathered on Friday to discuss Mr Mbeki's future, but failed to come to a decision - prompting speculation of a split within the party.

'There has never been a more powerful illustration of the leadership crisis within the ANC,' said the main opposition Democratic Alliance in a statement prior to Saturday's developments.

At issue has been a September 12 court ruling that cleared Mr Zuma of corruption charges and hinted that Mr Mbeki's government had interfered in the decision to prosecute him - an allegation that the president's office denied.

Fierce debate followed the judgment, along with speculation as to whether the ANC would force Mr Mbeki out in a vote of no confidence, ask him to resign, or allow him to serve out his term which ends in mid-2009.

The dismissal of the charges on a technicality cleared the way for Mr Zuma to stand for president in elections next year.

The main allegation against Mr Zuma had been that he received bribes for protecting French arms company Thint in an investigation into a controversial weapons deal.

Judge Chris Nicholson said on Friday the decision to throw out the case was not a reflection of Mr Zuma's guilt or innocence, but a technical decision based on his right to make representations before being recharged.

But the judge also hinted that Mr Zuma's complaints that he was the victim of a conspiracy had some merit, pointing to 'baleful political influence.'

Mr Mbeki fired Mr Zuma as deputy president in 2005 after his financial advisor was jailed for corruption. -- AFP