"The agreement has been signed," said Shai Bazak, spokesman for the Israeli Prime Minister, Benjamin Netanyahu, after a 90-meeting meeting that began after midnight between the Israeli leader and his Palestinian counterpart, Yasser Arafat.
The agreement, which caps four months of tortuous negotiators brokered by a US envoy, Dennis Ross, was reached at a summit on the Israel-Gaza border.
PLO officials said the initialling took place in a room without reporters. A public signing ceremony attended by Israeli and Palestinian leaders along with European, Arab and American representatives will be held on Friday.
PLO officials said the agreement stipulates an Israeli withdrawal from 80 per cent of Hebron within 10 days.
Mr Bazak said the agreement was signed by Israel's chief negotiator, Dan Shomron, and his Palestinian counterpart, Saeb Erekat, and that Mr Netanyahu and Mr Arafat were speaking by phone with President Bill Clinton.
Israeli troops will withdraw almost immediately from most of Hebron. The city has a population of 120,000, in the centre of which live 52 Jewish families. To protect them, Hebron will be partitioned, with 20 per cent of the city remaining under Israeli control. This part of the accord is little different from that signed by the last Israeli government in 1995.
Under a further part of the accord, brokered by King Hussein of Jordan at the weekend, Israel has promised to redeploy its troops on the West Bank and evacuate Palestinian villages in three stages, completing the withdrawal by 31 August 1998. This is a year later than agreed in the original Oslo Two accords, signed in 1995.
There is no understanding about the extent of the territory over which Israel is to cede control. Mr Arafat expects 90 per cent of the West Bank but Mr Netanyahu says Israel may only withdraw from half, keeping the Jordan valley, the desert east of Jerusalem and other "specified military locations". Vagueness about the extent of Israeli redeployment sets the scene for future political crises.
More immediately, Israeli and Palestinian leaders have to resolve other issues, including the extradition to Israel of Palestinians who have killed Israelis, the veto over appointments to the Palestinian police in Hebron and amendments to the Palestinian covenant, which Israel says urges Israel's destruction.
Also to be addressed in the accord are the Palestinian demands for the opening of a passage between Gaza and the West Bank, the release of prisoners and the Palestinian airport being built at Gaza.
Mr Netanyahu and his advisers are saying future redeployment hinges on the Palestinians fulfilling their part of the agreement. Such is the distrust that the US is to issue guarantees that the two sides will meet their commitments.
Mr Arafat'sstrategy of refusing to make an agreement on Hebron alone, but to demand dates for further Israeli redeployment from the villages, where 900,000 out of 1.3 million Palestinians on the West Bank live, appears to have paid off.
He is also on the verge of getting a commitment from a right-wing Israeli government to give up land on the West Bank, which many of its members see as the Land of Israel, the land God gave to the Jews.