It is slightly better for Zimbabweans that Robert Mugabe has agreed to talk to the opposition, rather than sending his supporters to harass, arrest and kill its members. But while he is still president — and his officials at the talks have declared that this is non-negotiable — it is hard to see any plan emerging which will rescue the country from the disaster of the last decade of his rule.

The power-sharing talks, which broke up over the weekend, resumed yesterday. Thabo Mbeki, South Africa's President, who is chairing them, has rightly been the target of scathing attacks internationally for declining to criticise Mugabe openly. He would find it a useful rebuttal to extract a deal from these talks before the regional summit which he hosts in South Africa on August 16.

But the talks appear to have stalled, unsurprisingly, on the question of exactly how to share power between Mugabe, as President, and leader of Zanu (PF), and Morgan Tsvangirai, leader of the Movement for Democratic Change (MDC), who boycotted the June elections after attacks on his supporters. Tsvangirai's strongest card, apart from international support, is that his party won most seats in parliament in the first round of the elections in April, despite widespread intimidation and violence.

But even though the talks have sketched out a crude framework of Mugabe as president, with Tsvangirai as prime minister, the dispute is over the extent to which Mugabe would be simply a figurehead, and would concede real executive power to Tsvangirai. The deal means little without that, and yet it is hard to imagine — given the uncompromising remarks from the Mugabe camp — that he will contemplate this.

Zimbabwe is hardly the only country facing that impossible division. In Pakistan, the impeachment proceedings against President Pervez Musharraf which began yesterday are triggered by precisely that point: his unwillingness to cede authority to the government elected early this year.

Kenya is the example that gives apparent encouragement. The power-sharing agreement between President Mwai Kibaki and Prime Minister Raila Odinga, of the opposition Orange Democratic Movement, was reached after elections last year that were marred by the deaths of more than 1,000 people, the displacement of more than half a million, and blatant ballot-rigging. Odinga handled with restraint the sharing of power after an election that many thought he had properly won. Since then, he has emerged as an impressive advocate and symbol of the possibility of negotiated solutions, although not one to Mugabe's taste. Odinga has called Mugabe "an embarrassment to the African continent" and said that the goal of talks should be to secure him a "safe exit".

But Zimbabwe is not Kenya. The comparison is cruel. Of course, the bitterness and violence of the Kenyan elections, and the potential for explosive conflict, was fuelled by ethnic conflicts which the government had exacerbated. But there was an impressive recent history of growing prosperity, which had made it one of Africa's success stories, and of comparatively good government — except when it came to the final test of being prepared to surrender power. There was no equivalent of Mugabe or his systematic attempt to annihilate the opposition, apparently indifferent to the destruction of one of Africa's most successful economies.

Talk of power-sharing implies that Mugabe can be constrained by the terms of such a deal — or even, as Odinga hopes, persuade to leave quietly. But this is a leader who has been indifferent to the suffering he has brought, almost revelling in the measurements of economic collapse in his eagerness to blame Britain and other supposed oppressors. The only encouraging point is that Mugabe would not be talking at all if he didn't recognise that the country's disintegration is undermining his support. But international investors and other governments are not going to pour in the cash Zimbabwe needs for reconstruction until he has gone. A plausible deal which might lead to Zimbabwe's rebirth does not have room in it for Robert Mugabe.

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