Visiting American diplomats pressed Prime Minister Ariel Sharon (search) on Thursday for more details of his proposed withdrawal from the Gaza Strip (search), as his top security advisers recommended Israel also dismantle as many as 24 settlements in the West Bank.

The proposed pullout from much of Gaza and parts of the West Bank is part of Sharon's plan to impose a boundary on the Palestinians, at least temporarily, if peace efforts remain frozen.

The prime minister has given few details, raising concerns in Washington and with the Palestinians that he may abandon the U.S.-backed "road map" peace plan. That strategy calls for an immediate end to violence and the creation of an independent Palestinian state alongside Israel by next year, but neither side has moved to implement it.

The U.S. diplomats arrived for a two-day visit to hear more about the withdrawal plan, said Paul Patin, spokesman for the U.S. Embassy.

Sharon's office said the prime minister met with the Americans for more than three hours, and further talks would take place Friday.

In Washington, State Department official David Satterfield said the envoys were insisting that Sharon take steps within the framework of the "road map" and contribute to creation of a Palestinian state.

Sharon's proposals "should move us toward that goal, not complicate it," said Satterfield, the deputy assistant secretary of state for the Near East.

The U.S. team, making a second visit to Israel in less than a month, included Assistant Secretary of State William Burns; Stephen Hadley, deputy director of the National Security Council; and Elliot Abrams, a Middle East specialist at the council.

The trip coincided with confirmation of a newspaper report that Israel is considering leaving up to 24 West Bank settlements.

A senior Israeli official, speaking on condition of anonymity, said Sharon's national security team had recommended the partial West Bank pullback and a withdrawal from virtually all of Gaza.

Sharon has not yet decided on the scope or timing of any withdrawal, the official said.That will depend on how Egypt, Jordan and the United States reacts to the plan, he said.

Any broad Israeli withdrawal would be with the understanding that large settlement blocs in the West Bank would not be included. About 230,000 Israelis live in some 150 West Bank settlements.

Egypt, which borders Gaza, has emerged as a key player in the withdrawal plan.

Israeli Foreign Minister Silvan Shalom sought support in Cairo on Thursday, particularly Egyptian help in keeping the volatile area quiet if Israel pulls out.

While both sides ruled out an Egyptian military presence in Gaza, Shalom said that Israel would welcome an Egyptian role along the border, regardless of whether there is a withdrawal.

"We would like in any case that the border would be guarded by Egypt, and if that requires of them more effort, that will be discussed in the near future by the two countries," Shalom told Israel Radio after meeting Egyptian President Hosni Mubarak (search).

Israel has carried out numerous military operations along the border to stop the flow of illegal weapons through tunnels into Gaza. It fears even more weapons could enter Gaza once it leaves the area.

Interviewed on Israel TV, Mubarak said Egyptian police have "already closed many tunnels" and that it was Israel's responsibility to stop smuggling at the other end.

The meeting came amid a flurry of diplomatic activity. On Wednesday, Egypt's intelligence chief traveled to the West Bank for talks with Palestinian leader Yasser Arafat (search). Next week, the Israeli and Palestinian prime ministers are expected to hold their first summit.

Palestinians have responded cautiously to a Gaza withdrawal. They fear Sharon wants to dig in to the parts of the West Bank it does not leave, frustrating their hopes of a state in all of Gaza and the West Bank with a capital in east Jerusalem.

Arafat on Thursday said he would welcome a Gaza withdrawal, but insisted it would have to be accompanied by a simultaneous pullback from the West Bank.

However, the withdrawal "should be through talks between the two parties and the framework of the road map," he told Palestinian legislators. Sharon has spoken of unilateral steps.