Zimbabwe's opposition leader Morgan Tsvangirai was in South Africa Tuesday for talks with negotiators from his Movement for Democratic Change (MDC) on the suspension of talks with President Robert Mugabe's Zanu-PF.

Tsvangirai's spokesman George Sibotshiwe confirmed that the MDC leader was in South Africa, where multi-party talks on the formation of a unity government have been taking place under South African mediation.

'All I know is that our president is due to be briefed by his negotiators today,' Sibotshiwe said.

Representatives from Zanu-PF and two factions of the MDC - the majority faction led by Morgan Tsvangirai and a smaller faction led by Arthur Mutambara - began talks Thursday last week on the formation of an 'inclusive' government, as called for by the African Union at a summit in June.

On Monday, the MDC said the talks had been suspended, with party officials in Zimbabwe saying privately an impasse had been reached over the division of power in a powersharing government.

Deputy Zimbabwean Information Minister Bright Matonga said the only person who could comment on the talks suspension was southern Africa's mediator in Zimbabwe, South African President Thabo Mbeki.

'The MOU (memorandum of understanding on the talks) is very clear that neither of the parties must talk to the press,' he stressed.

According to MDC sources, the position that Tsvangirai would occupy is a key bone of contention.

The MDC, with strong backing from Britain and the United States, has been pushing for Tsvangirai to have the leading role in any powersharing arrangement. The party has proposed that Mugabe remain on as president but with reduced powers and that Tsvangirai occupy a new role of executive prime minister.

The MDC defeated Zanu-PF in March parliamentary elections, and Tsvangirai took more votes than Mugabe in the first round of voting for president on the same day.

But Zanu-PF has ruled out Mugabe having anything other than a leadership role in the new government, saying he is the rightful leader.

Mugabe was inaugurated as president for a further five years in June after winning a presidential election run-off he alone contested. Tsvangirai boycotted the poll over the killing of dozens of his supporters by Mugabe-loyal youth militia.