South Africa and Britain are supporting efforts by U.N. Secretary General Kofi Annan to find a solution to the political crisis in Zimbabwe.

The issue of what to do about Zimbabwe and its leader, Robert Mugabe, came up in talks in London between South African President Thabo Mbeki and British Prime Minister Tony Blair.

The men told a news conference they hope U.N. Secretary General Kofi Annan can broker a settlement to the political crisis that has also wrecked Zimbabwe's economy.

Mr. Blair says there is only so much that can be done by Britain, the former colonial power in Zimbabwe often blamed by Mr. Mugabe for his country's troubles.

"I welcome the fact that the United Nations secretary general has indicated that he wishes to be involved in this," said Tony Blair. "He will provide, I know, a wholly independent assessment of the situation there. For the people in Zimbabwe, of course, I want to see progress made, but I think if you look back at these last few years the reasons why you've got those social and economic problems don't rest here, but back there."

President Mbeki said it would be counter-productive to offer outside advice on how to resolve the Zimbabwe crisis as Mr. Annan pursues his initiative.

"I'm quite certain that it would not help in any way if any one of us started prescribing what we believe ought to be the outcome of the process," said Thabo Mbeki. "I think it is best left to the U.N. and the Zimbabwe government and hopefully that will produce an outcome so that we remove this particular matter from the international agenda."

News reports from South Africa have said Mr. Annan could propose incentives to Mr. Mugabe - such as international aid and amnesty from prosecution - if the Zimbabwean president retires.

The Blair-Mbeki talks were held in the framework of the seventh bilateral forum of Britain and South Africa. The highlight was an $8-million trade deal to stimulate commerce between Britain and southern Africa, and between South Africa and its neighbors.