His growth to prominence coincides with a spell of relative calm as Mr Arafat acts with rare determination to shore up his December 16 ceasefire call and Palestinian opinion swings gradually behind him.

Senior Palestinian Liberation Organization official Sari Nusseibeh, (R), meets Israeli Labour Party parliamentarians Yossi Beilin, (L), and Yael Dayan, (C), in Tel Aviv on December 21, 2001. Nusseibeh spoke to Labour Party member's days after Israeli police hauled him in for questioning after he arranging a reception for foreign diplomats in Jerusalem. Husseibeh is a leading Palestinian moderate who has angered some Palestinians by suggesting they should give up the right of refugees to return to their homes lost in the 1948 Arab-Israeli war. REUTERS/Havakuk Levison

Yesterday Washington acknowledged Mr Arafat's efforts by announcing that its envoy, General Anthony Zinni, will return to the region. He will press Mr Arafat to crack down on the militants of Hamas and Islamic Jihad the Israeli prime minister, Ariel Sharon, to implement a ceasefire plan.

After a rocky start in the autumn as the Palestinian representative in Jerusalem, Mr Nusseibeh hit his stride last week, presiding at an unusually hopeful gathering of Israeli and Palestinian peace activists at a hotel in the old walled city.

More than 900 academics, activists and politicians signed a peace declaration - unthinkable a few months ago, when the Israeli left seemed to be collapsing and Palestinians were wary of being seen as cooperating with Israelis.

"I don't believe the last 15 months should depress us or blind us to the fact that peace is possible among us," Mr Nusseibeh said, slouching with a cigarette against the hotel bar, in a throng of delighted Israeli peace activists.

It was the message that the mainstream Israeli left had been yearning to hear: an appeal for reconciliation after a time when the voices of extremism on both sides drowned the spirit of compromise.

Other Palestinians have maintained a dialogue with such Israeli moderates as the Labour party former minister Yossi Beilin, and the Israeli military establishment has its pet Palestinian security officials, but Mr Nusseibeh exercises a peculiar charm.

He is scholarly and urbane, the offspring of a clan whose roots in Jerusalem go back 1,000 years: a Muslim family whose members are the traditional custodians of the Church of the Holy Sepulchre.

He went to Oxford and Harvard and is married to a Briton.

After pioneering peace talks with the Israelis at Madrid a decade ago, he retired to academia at Jal-Quds University in Jerusalem. His political seclusion ended when Mr Arafat named him to replace Faisal Husseini, who died of a heart attack last summer.

Apart from his pedigree, Mr Nusseibeh engaged the Israeli imagination - as well as that of foreign diplomats and journalists - by daring to question the idea of returning Palestinians to their original homes in what is now Israel. To Palestinians, the right to return is sacrosanct. To Israelis, it means the slow death of their state through the loss of their majority.

"As Palestinians, we have to come to terms with the fact that if we want a two-state solution it is clear we are not going to be able to implement the dream of returning these millions of people," Mr Nusseibeh said in an interview at his university office.

In return for the Palestinians giving up their "unrealistic" demand, Israelis would have to accept the fact of Palestinian rights in East Jerusalem, which has been occupied by Israel since 1967, and the destructive impact of the illegal Jewish settlements in the West Bank and Gaza.

"They will have to come to terms with the fact that they cannot reach peace with us while keeping the settlements intact, because they will not lead to an Israeli state and a Palestinian state but two Israels," he said.

"These are conceptual hurdles that have to be overcome by the two publics. We have allowed ourselves to continue dreaming unrealistically. We have to face these issues."

His ideas have been disowned by fellow Palestinians, and though he has been chipping away at their disapproval, it is far from certain that his moderate vision can win a broad following.

Equally, the Israelis may be disappointed if they bank too much on Mr Nusseibeh and his generation as the means of bypassing Mr Arafat. But this apart, both may be nearing the point where new beginnings are thinkable, and Mr Nusseibeh, for the moment, embodies that hope.

"People are coming to their senses. We can't just remain in this quagmire of hatred and enmity," he said. Mr Arafat's December speech "was a kind of knocking sense into people".

"People have begun to think and act in a new way. Instead of thinking suicide attacks are wonderful things, they have begun to think they are counterproductive. Mr Arafat has begun to put the public mood back in order."

© Guardian Newspapers Limited 2002

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