British Prime Minister Tony Blair believes a deal for a UN Security Council resolution to end the fighting in Lebanon is possible within 24 hours.
A statement from his office this evening said: "The prime minister believes that there is the potential for an agreement within 24 hours."
Mr Blair, on holiday in the Caribbean, has sent Foreign Secretary Margaret Beckett overnight to New York for talks.
"I am travelling to New York to reinforce my efforts, working closely with my Foreign Ministerial colleagues, to reach agreement on a resolution which would bring about a cessation of the violence in Israel and Lebanon," Ms Beckett said in a statement.
The United States and France earlier announced that an agreement was close, though US Ambassador John Bolton was reluctant to make any predictions.
French Foreign Minister Philippe Douste-Blazy said in Paris he expected an agreement soon. "Things are moving in New York today. I hope they move even more quickly and in the hours to come," he told reporters. "We expect, from one moment to the next, an accord in New York."
But Mr Bolton, was more guarded. "It is entirely possible we could have a vote tomorrow (Friday)," he said. "But I wouldn't put odds on it."
The text has not been distributed yet to the 15-member council which usually studies it for 24 hours before a vote.
Smoke rises after an Israeli air strike on Baalbeck town, eastern Lebanon today.
The key obstacle was to agree on a timetable for Israel's withdrawal from a narrow strip of southern Lebanon.
France wants Israel to begin withdrawing 10,000 troops as soon as the Lebanese army and a UN peacekeeping force deploys in south Lebanon, now controlled by Hizbullah's militia.
The United States, which supports Israel's position had argued that Israel could keep troops in Lebanon until the arrival of a larger and better-armed international force, which France may lead.
Earlier today Hizbullah hit at least two Israeli tanks with rockets and mortar bombs near the town of Marjayoun during fierce fighting in the area after a major Israeli incursion.
Hizbullah said it had killed 18 Israeli soldiers, wounded several others and destroyed 16 tanks in battles across southern Lebanon. There was no immediate word from the Israeli army.
The Israeli incursions continued this morning despite reports that Prime Minister Ehud Olmert had decided to put an expansion of operations in the region on hold, to give US-led efforts to curb Hizbullah a chance.
Mr Olmert's security cabinet yesterday approved plans to make deeper incursions, possibly to the Litani river, up to 13 miles from the border. A senior political source said the expanded offensive could last 30 days.
The clashes at Marjayoun tapered off in the afternoon, witnesses said.
An Israeli force near Marjayoun headed towards the Shi'ite Muslim town of Khiam to the southeast, sparking battles with Hizbullah fighters dug in and around the town, residents said.
Israeli planes and artillery pounded Khiam as battles raged. Despite the Israeli advance, Hizbullah fired dozens of rockets at northern Israel from hills in the area, killing a woman and her toddler son.
Witnesses said Israeli soldiers were entering and leaving residential areas in Marjayoun, Qlaia and Burj al-Molouk, after imposing a curfew. The priest of the area's main church pleaded over its public address system for people to stay indoors and keep away from windows.
Israeli soldiers later conveyed the same message via loud hailers.
"On the main road, we do not see anything but can hear a lot. We cannot see any tanks or soldiers on the main road, but the sounds we hear are very disturbing," Marjayoun Mayor Fouad al-Hamra told Al Arabiya television by telephone.
Israeli soldiers also went into the Marjayoun barracks, where about 600 Lebanese army soldiers and policemen are based. Lebanese sources said the Israelis enquired about the men's weaponry and asked the Lebanese not to leave the barracks.
The Israeli army today said that 15 of its soldiers and 40 Hizbullah guerrillas had been killed yesterday, one of the bloodiest days of fighting.
Israeli television said early today that the bodies of Iranian Revolutionary Guards had been found among guerrillas killed in south Lebanon. Hizbullah denied the claim.
The war has killed at least 1,011 people in Lebanon, mostly civilians, and more than 121 Israelis.
Agencies