President Bush says Palestinian Leader Yasser Arafat must do "everything possible" against terrorists responsible for a series of suicide bombings in Israel.

White House spokesman Ari Fleischer says President Bush wants to see more action from Mr. Arafat to crack down on militants attacking Israeli civilians.

"Chairman Arafat needs to do more to bring about a secure environment in the Middle East. The President is interested in results, and the President will be looking to make certain that Chairman Arafat takes enduring, long-term, real, and meaningful actions so the terrorists who are trying to interrupt the peace process in the Middle East will not be successful," he said.

Since Mr. Arafat declared a state of emergency Sunday, 180 people have been arrested by Palestinian authorities, most from the Islamic Jihad or the radical Palestinian group Hamas, which claimed responsibility for the recent suicide bombings that killed 25 Israelis and wounded 200 others.

Mr. Arafat's security forces clashed with Hamas supporters after placing the group's spiritual leader under house arrest in the Gaza Strip. Mr. Fleischer says the arrest of Sheik Ahmed Yassin shows there is "some progress" on Mr. Arafat's part, but he says President Bush is looking for a "lasting"commitment to peace with efforts that can be measured.

Mr. Fleischer says Mr. Arafat can continue to do more against terrorism by prosecuting those arrested instead of eventually turning them loose. He says President Bush remains "deeply concerned that Palestinian jails are built with bars in the front and revolving doors in the back."

Israel has also dismissed the Palestinian arrests as a "token," raising the possibility of more Israeli air strikes against Palesitinain targets.

Egyptian Foreign Minister Ahmed Maher met with top Israeli and Palestinian officials to try to end the 14-month uprising. President Bush spoke on the telephone with Egyptian President Hosni Mubarak. Mr. Fleischer says Mr. Bush praised President Mubarak's "courageous leadership" in trying to end Middle East violence.

The Bush Administration's own mediator, retired General Anthony Zinni, continued meeting with both sides in hopes of forging a ceasefire.