The Bush administration is calling on the Palestinian authority to move against radical groups, following Tuesday's twin suicide bomb attacks against Israelis. Secretary of State Colin Powell says the bombings must not be allowed to de-rail efforts to implement the "road map" to Middle East peace.

U.S. Middle East diplomacy has been complicated not only by Tuesday's suicide attacks but also a resurgence of violence along the Israel-Lebanese border.

But in an emotion-filled address to an audience of Israeli and Palestinian students here, Secretary of State Powell said the he and the Bush administration will never stop working to resolve the Middle East conflict.

The secretary told the youth group "Seeds of Peace" that the bombers are trying to "destroy the dreams" of Israelis and Palestinians but said they must not be allowed to de-rail the international "road map" to a peace accord by the end of 2005.

"We cannot let it go off track. We will continue to move forward on the road map. We will continue to do everything we can, both as the United States of America but also working with the Quartet members that you've heard about, the Russian Federation, the European Union and the United Nations, as well as working with leaders in the region, Arab leaders in the region and with Prime Minister Sharon and Prime Minister Abbas, and all others who are committed to peace to come together and once again say we will go forward. We will not be stopped by bombs. We will not be stopped by this kind of violence," he said.

Later, both the White House and State Department condemned the suicide attacks, the first of their kind in five weeks, in the strongest terms and urged the Palestinian Authority to move against radical factions responsible for acts of terror.

State Department spokesman Philip Reeker said there can be no excuse for the violence Israeli civilians have been forced to endure, and said the twin attacks illustrate why a temporary cease-fire by extremist groups is insufficient.

"The Palestinian Authority, as we've said, must act now to dismantle terrorist capabilities, to dismantle the capacity of these terrorist organizations, these enemies of peace and the networks that perpetrate such attacks, and work to prevent any future attacks. As we've said before, and as the road map made clear, all parties have responsibilities in bringing peace to the Middle East. But ending terror must be the highest priority," he said.

The two suicide attacks, which came within 40 minutes of each other, coincided with a mission to the area by the Bush administration's senior Middle East envoy, Assistant Secretary of State for Near Eastern Affairs, William Burns, who held talks with top Israeli and Palestinian officials.

Mr. Burns is due to go on to Jordan for more discussions Wednesday.