President Mugabe is most likely to be overthrown by people from within his own party, not Zimbabwe’s bruised and battered opposition, US and British officials said yesterday.

“I believe 2007 is likely to be a tipping point,” one senior Foreign and Commonwealth Office official said. The chaos could send two million more refugees pouring into South Africa. The rising alarm of Zimbabwe’s neighbours may offer the best hope of managing the crisis, he added.

In the deteriorating situation, none of the options is good. It is still possible, many acknowledge, that Mugabe might cling on. “He is far from giving up,” Christopher Dell, the US Ambassador to Zimbabwe, said. “He’s not prepared to go down without a fight but he is weaker than he’s ever been before, because the economy has made him weaker and because everyone recognises that he’s 83 years old.”

Zanu (PF), his party, has rebelled for the first time and denied him a term extension of three years, until 2010. But he might decide to call his opponents’ bluff and run for another six-year term in 2008.

However, speculation is growing fast that he may be ousted by a “palace coup” from within his party. “There is a new mood in the country and I think it has reached a tipping point,” a Foreign Office official said yesterday. “But we have not had a mass uprising — the most the MDC [Movement for Democratic Change] has managed to get on the streets is a couple of hundred,” he added.

Instead, his most likely challenge may come from either of Zanu (PF)’s rival factions: those supporting Emmerson Mnangagwa, the former parliamentary Speaker, or General Solomon Mujuru, the former Armed Forces chief, and his wife, Vice-President Joyce Mujuru. Western officials say that none of these is a saint, and may be tainted by association with Mugabe’s excesses. But the hope is that they would still be easier to work with than Mugabe.

South Africa, long reluctant to criticise Mugabe, has also become more alarmed by the influx of refugees fleeing economic collapse. There are already an estimated two or three million within its borders, and a worsening of the crisis could almost double the numbers, analysts argue. South Africa is concerned that this could jeopardise its hosting of the World Cup in 2010, an official said.

China, which has seen Zimbabwe as a source of resources and an outlet to southern Africa for its goods, is also so alarmed by the threat of instability that it may break with past habits and add to pressure on Harare. It has been one of Zimbabwe’s best allies in the United Nations Security Council, but that may be fading, officials say.

It is hard for other countries to bring about their preferred option: a managed transition. Mugabe’s sudden death could be far from the best option: it would bring a contest, and perhaps more turmoil, a British official said. “Mugabe falling off his twig would be a complicating factor.”

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