A hugely controversial figure best known for his promotion of illegal Jewish settlements on Palestinian land and his ill-fated 1982 invasion of Lebanon, Mr Sharon had reinvented himself in recent years. Staging a remarkable political comeback, he had also reshaped Israeli politics, creating a centrist party that seemed favoured to win the March general elections.

His vision of a final settlement with Palestinians was an imposed one. It was unlikely to be accepted by Arabs or to create the durable peace that the people of the region are yearning for. But his decision to remove Jewish settlements from the Gaza Strip in August created rare political momentum. The Gaza withdrawal earned him international praise and bolstered American support for Israel to retain parts ofthe West Bank in any future peacesettlement.

But Mr Sharon has been a one-man show, a general turned politician who was able to convince Israelis that only he could bring security to the Jewish state. He has no obvious successor. Without him, the future of Kadima, the new party formed after his sudden defection from the rightwing Likud party, is thrown into serious doubt.

The outcome of his likely political demise may well be that Israel reverts to the historic divide between the rightwing Likud, opposed to returning territory to the Palestinians, and the pro-peace Labour party. So far, opinion polls suggest Amir Peretz, the new Labour leader, has failed to inspire voters, potentially leaving Benjamin Netanyahu, the hardline Likud leader, with the greater advantage.

That Mr Sharon's grave illness coincides with growing political turmoil in Palestine compounds the international anxiety over the Middle East. The Gaza Strip has been wracked by lawlessness and violence in recent weeks, further weakening the Palestinian Authority of Mahmoud Abbas. The radical Hamas meanwhile is expected to mount a strong challenge to Mr Abbas' Fatah movement in elections scheduled for later this month. Rising pressure on the Palestinian Authority could provoke a delay in the poll.

The almost certain end of the Sharon political era makes a troubled Middle East all the more unpredictable. But uncertainty could also represent an opportunity. Having essentially ad-opted Mr Sharon's strategy towards the Palestinians in recent years, the US and Europe may now be forced to return to more active and creative engagement to revive negotiations on a just and lasting Israeli-Palestinian peace settlement.