Jerusalem ? Mahmoud Abbas headed to Washington on Tuesday for the first meeting between Palestinian and American leaders since U.S. efforts to broker an Israeli-Palestinian peace treaty broke down in late 2000.

Abbas wants assurances from President Bush of U.S. help in halting Israeli settlement building and keeping the peace process moving after Israel’s planned withdrawal from the Gaza Strip this summer.

Many Palestinians have low expectations, however. “We will lay down our fears and anxieties … and express the really urgent need of American support,” Deputy Prime Minister Nabil Shaath said.

Abbas meets with Bush on Thursday, part of a three-day trip to the U.S. capital during which he will speak to lawmakers, Jewish and Arab-American leaders, and senior officials.

The Palestinian leader said he would ask the United States to push ahead with the internationally backed “road map” peace plan, which calls for the eventual establishment of a Palestinian state.

“When I talk about political demands, I mean the road map,” Abbas said before leaving.

White House support could bolster the Palestinian position in peace talks with Israel, and more immediately, strengthen Abbas’ stature ahead of crucial Palestinian parliamentary elections scheduled for mid-July. Hamas militants warned Tuesday that they might end an informal truce with Israel if Abbas delays the elections, as he is considering.