Few issues before the White House are as complicated as the Middle East peace process, where each word, each nuance, is watched carefully. President Bush's decision to endorse Israel's so-called disengagement plan offers dramatic proof.

President Bush said he supports Israel's plan to withdraw settlers from the Gaza Strip and four remote West Bank settlements, but at the same time he added that it is unrealistic to expect a total Israeli pullout from occupied territory. "The realities on the ground and in the region have changed greatly over the last several decades, and any final settlement must take into account those realities and be agreeable to the parties," he said.

He spoke after talks at the White House with Israeli Prime Minister Ariel Sharon. The normally gruff Israeli leader smiled as he listened to the president's words. He said, "You have proven, Mr. President, your ongoing deep and sincere friendship to the State of Israel and to the Jewish people."

There was elation in Israel and anger in the Palestinian territories. Palestinian negotiators have long demanded a total withdrawal from all occupied territory, as well as a promise that Palestinian refugees will be able to go back to their homes in what is now Israel.

President Bush was the first U.S. president to suggest in public that there will be no return to the borders that existed before the 1967 war, even though such ideas have been discussed privately. So have the notions that some West Bank settlements will remain, and the refugees will find a home in a new Palestinian state rather than on Israeli soil. However, Palestinian Prime Minister Ahmed Quriea was outraged.

"This we cannot accept," he said. "Unfortunately, this will not help the peace process, will not help peace between the Palestinian and Israeli people, and I am sure this will not help stability in the region."

Administration officials urged the Palestinian leadership to study the president's words more carefully. These officials, who spoke on the condition they would not be identified, stressed the president continues to believe the thorniest issues of all, borders, settlements, and the fate of the refugees, will ultimately be resolved through negotiations. They said Mr. Bush saw the Israeli withdrawal from Gaza as a way to breathe new life into the peace process.

However, some foreign policy analysts have doubts. Henry Siegman is with the New York-based Council on Foreign Relations. He says by backing Prime Minister Sharon's unilateral withdrawal plan, the president is providing little incentive for the Israelis to negotiate. "Palestinians want to return to the negotiating table," he said. "There is no chance, as I see the situation, that Prime Minister Sharon will ever return to the negotiating table."

Philip Wilcox, a former senior U.S. diplomat in Israel, said he believes talks will resume, though he adds America's reputation as an honest broker may be damaged.

"At some stage, the Israelis and the Palestinians will have to talk to each other," he added. "There will have to a very strong American role in that process. This is a setback, in my view, but things can change and it would be wrong to say that the situation is hopeless."

Mr. Wilcox currently heads the Foundation for Mideast Peace here in Washington. He believes many factors may have played into the president's decision to back Ariel Sharon's plan, including the fact that both Israel and the United States have been victims of terrorism. "But I think the president if he is going to succeed, or any American president is going to succeed, will have to show equal empathy and support for the Palestinians," he said.

That is the message President Bush is likely to hear next week from Jordan's King Abdullah. The Jordanian monarch comes to the White House for talks on Wednesday.