The United States is trying to defuse a water dispute between Israel and Lebanon which Israel has said could lead to war.

An American water expert has held talks with Lebanese leaders in Beirut, to discuss the project aimed at diverting water from the Wazzani, a border river.

The Wazzani is a tributary of the Hasbani river which flows into the Jordan - a major source of drinking water for Israel.

Israeli Defence Minister Binyamin Ben Eliezer has said the Hasbani water system provides 10% of his country's water, and that Israel could not tolerate a diversion.

Richard Lawson, a State Department water expert, had talks with Lebanese Prime Minister Rafiq Hariri and Parliamentary Speaker Nabih Berri on Wednesday.

'Sensitivity'

No details of the meetings have emerged. Mr Lawson is due to meet Israeli officials later this week.

The move follows a visit to southern Lebanon on Monday by another US water expert, Jim Franckiewicz, to determine if work on the Wazzani - which has already started - was consistent with regulations and agreements over the years.

The dispute could plunge the two countries into war

On Tuesday, Israeli Foreign Minister Shimon Peres brought up the issue in a meeting with US Secretary of State Colin Powell at the United Nations in New York.

"We understand the sensitivity of the issue but we don't want to see a new crisis developing over the diversion of water out of the river," Mr Powell said.

Lebanese President Emile Lahoud has said the project will continue and officials insist Lebanon is not is breach of any international agreements.

The leader of Lebanon's militant Hezbollah group - which controls southern Lebanon - says the group will resist militarily if Israel uses force to stop the scheme.

Border tension

Last week Israeli Prime Minister Ariel Sharon said Lebanon's Wazzani plan could be a cause for war between the two countries.

The Israeli army has been closely monitoring the work from their side of the border.

The Hezbollah controls the Lebanese side of the river

The AFP news agency says Israeli soldiers on Wednesday threatened to fire on Lebanese labourers when the engineer leading the project knocked over a UN border marker.

The soldiers pulled out after UN troops arrived to prop up the marker, according to AFP.

In 2001, Lebanon went ahead with a pumping project from Hasbani river to irrigate the drought-stricken border village of Ghajar, despite strong Israeli objections.

Beirut says the plan is to take less that 10 million cubic metres from the Wazzani, which it says falls within its fair share of water according to international law.

Lebanese officials say the Wazzani's annual flow is 50 million cubic metres a year, and the Hasbani's flow is 150 million cubic metres.