Secretary of State Madeleine K. Albright and her top Middle East peace negotiators sought early today to restart stalled negotiations on a long-delayed Israeli troop withdrawal from the West Bank that is seen as critical to restoring trust between Israel and the Palestinians.

U.S. officials had hoped for an agreement to resume implementation of the 10-month-old Wye River accord in time for Albright and Egyptian President Hosni Mubarak to preside over its signing at a ceremony Thursday afternoon in Alexandria, Egypt. But Israel and the Palestinians, although agreeing on a withdrawal schedule and other issues, remained deadlocked on a seemingly small difference over the number of Palestinian prisoners Israel is to release as part of the accord.

As a result, Albright softened her resolve not to become involved in mediation and stepped into the standoff. After telephoning Israeli Prime Minister Ehud Barak from Alexandria, she held an unscheduled meeting there with Palestinian leader Yasser Arafat and then flew to Jerusalem for a post-midnight huddle with Barak. Although she continued to emphasize that Israel and the Palestinians should work out their differences themselves, she also acknowledged that a U.S. role could be critical in the hours and days ahead.

"The United States will play the appropriate pragmatic role," Albright said at a brief joint news conference Thursday night with her Egyptian counterpart, Foreign Minister Amr Moussa, before leaving Alexandria. "We will do what needs to be done."

U.S. officials said they have no wish to repeat the hands-on role in the peace process they played during the administration of Barak's predecessor, Binyamin Netanyahu, when U.S. Middle East envoy Dennis Ross was once called upon to intervene in a dispute over the size of a Palestinian motorcade.

By all accounts, President Clinton and Barak got on well during Barak's visit to Washington in June, and the White House welcomed his request for a reduced American role in negotiations with the Palestinians -- in part because U.S. officials are reluctant to pressure their close ally to carry out the Wye River agreement. But it also seemed clear that the United States is unlikely to sit on the sidelines if the peace process shows signs of faltering.

At the entrance to Mubarak's lavish seaside palace in Alexandria early Thursday evening, Albright and Ross talked outside a black sedan, poring over documents as she prepared to head into her meeting with Arafat. Throughout the day, Egyptian and American officials in Alexandria were on the telephone to top Israelis in Jerusalem in an attempt to bridge the negotiating gap.

Whatever the substance of those private conversations, the Israelis adopted a uniformly hard-line posture in public. Negotiations were over, they said, and it was up to the Palestinians to accept the new deal or suffer the consequences.

"We're not looking for softening from the Palestinians," said a top Israeli negotiator. "We're looking for direct, clear, well-stated answers. It's not a negotiation here."

Haim Ramon, an Israeli government minister who has also been involved in the talks, said Israel will not be swayed by Albright's visit.

"It's stupid to involve the Americans," he said. "They don't want to be involved in it, and we don't want them to be involved. If the Palestinians want it, they are making a mistake because we are not going to negotiate with the secretary of state."

After Barak's meeting with Albright, his office issued a statement early today saying no deal had been finalized. It said, however, that Israel was expecting some answers from the Palestinians today on several questions, and Barak's spokesman, David Ziso, called the talks with Albright "very good."

"The Americans are continuing their efforts to facilitate an end to negotiations with the Palestinians that would allow an agreement to be signed," the statement said.

The Wye accord, which called for Israel to withdraw its troops from a further 13 percent of the West Bank, is another iteration of several previous land-for-peace agreements signed with the Palestinians since the breakthrough Oslo accords in 1993.

Netanyahu carried out the first phase of a three-stage withdrawal agreed to last October at the Wye River Plantation in Maryland, but he suspended implementation of the accord soon afterward, deepening the freeze between the sides.

Since Barak's election in May, the Palestinians have insisted that he move quickly to implement the deal, which he has pledged to carry out and which they regard as a tangible measure of his commitment to the peace process. The U.S.-brokered agreement has thus assumed a symbolic significance that far transcends its limited scope.

Having cast himself as a peacemaker in the mold of slain Israeli prime minister Yitzhak Rabin, Barak has vowed to implement the accord one way or another, and the two sides appeared to have narrowed their differences on a range of issues. But they remain divided on the prisoner issue, with Barak insisting he will not release Palestinians held for killing Israelis.

"Sometimes issues are out there and everyone thinks, `What's the holdup?' And, in fact, it tends to be more complicated," said a senior U.S. official seeking to explain the standoff.

At the highest levels, there was an atmosphere of suspense about the negotiations. But on the street, Israelis and Palestinians were less excited. If they were exercised about anything, it was the prisoner question. Many Israelis regard many of the prisoners as terrorists, and the idea of freeing any of them is painful.

"I don't really think we should release prisoners with blood on their hands; it's not fair," said Orit Itcher, 32, a civil servant in Jerusalem. "But if it really comes down to it, peace is more important than fair."

But to the Palestinians, the same inmates are regarded as freedom fighters and prisoners of war.

"The release of 400 prisoners is a good step -- at least 400 mothers will be happy and get to see their children," said Abdel Rahman Jarada, the owner of a kitchen supply store in Gaza City. "But we hope that in the course of the negotiations Israel will release all the rest of the prisoners."