A top army officer began work at the head of a committee that will hone details of a unilateral partition plan that Prime Minister Ariel Sharon has vowed to enact if there is no progress on talks with the Palestinians.

The International Court of Justice at the Hague -- also known as the World Court -- starts hearings next month in response to a UN General Assembly request to rule whether Israel must tear down the barrier.

Israel's High Court will also hold a hearing before then on the legality of the barrier, built of razor wire and concrete.

"It was the recommendation of the attorney-general that if there are not changes to the route then it will be difficult to defend," said one senior political source. "This is what is being discussed, but there will not be major changes."

The Jewish state says completed sections of the barrier are already keeping out suicide bombers like those who killed hundreds during more than three years of conflict.

Palestinians call it an "Apartheid Wall" whose purpose is to grab land that Israel has occupied since 1967. Designed to loop around Jewish settlements, it cuts deep into land that Palestinians want for a state.

Even Israel's main ally, the United States, has criticised the route. The political sources said Sharon's cabinet chief would go to Washington this week to try to reach an understanding on some of the more controversial sections.

There have already been minor tweaks to the route. Israelis said they were to make life easier for Palestinians.