In his first telephone conversation with Abbas, also known as Abu Mazen, Bush reiterated his vision for "two states living side by side in peace," White House spokesman Ari Fleischer told reporters.

"The president stressed the need for all parties to take concrete steps and called for cooperative efforts between all Arab parties and Israel to create the conditions for peace and security in the Middle East," Fleischer said.

"Abu Mazen told the president he was committed to reform, to peace, and to ending all acts of terror," Fleischer said.

The 15-minute telephone conversation followed five suicide bombings in Israel and the Palestinian territories in a 48-hour period. It also came on the day that Sharon originally had been scheduled to visit Bush at the White House.

The Israeli leader's trip was postponed because of the bombings, and the White House said it was unlikely that Sharon would make it to Washington before Bush travels overseas at the end of next week on stops that include Poland, Russia and France.

Later in the day, Bush also spoke with Sharon to talk about the importance of remaining committed to the peace process in the Middle East, to working forward on the "road map" peace plan, Fleischer said.

"The president informed the prime minister of his call with Abu Mazen and told the prime minister that he believes Abu Mazen is a reformer who will work for peace," Fleischer told reporters.

Bush also told Sharon that "the United States is committed to the security of Israel and the prime minister thanked President Bush for his courage and his leadership," Fleischer added.

Sharon said that he is determined to move forward with the peace process, but that the only way to do so is for terror to be beaten, according to the prime minister's office in Jerusalem.

The "road map," created by the United States, the European Union, Russia and the United Nations, lays out steps for the two sides to take, with the aim of establishing a secure Israel and independent Palestinian state by 2005.

Sharon has said he wants to see some changes to the "road map," while Abbas has said he has reservations but will accept it as is.

During Tuesday's conversation with Bush, Abbas asked Bush to push Israel to begin implementing the "road map" and Bush promised he would do all he could to advance the plan, a Palestinian official said.

Fleischer said Bush considered Tuesday's phone conversation with Abbas as "friendly and hopeful" and looked forward to more telephone conversations with the Palestinian prime minister, but he gave no date.

(Xinhua News Agency May 21, 2003)