Secretary of State Colin Powell held critical talks with Israeli and Palestinian leaders on Sunday but emerged with no sign of progress in persuading them to begin implementing a peace "road map." Powell, leading the highest-level U.S. peacemaking effort in more than a year, tried but apparently failed to squeeze concessions from Prime Minister Ariel Sharon and Palestinian Prime Minister Mahmoud Abbas for ending 31 months of intifada. Each side insisted the other move first in putting the U.S.-backed plan in motion, a recipe for stalemate in a conflict that has defied numerous earlier diplomatic peace initiatives. Powell planned consultations with envoys of Washington's partners in the peacemaking Quartet -- the United Nations, European Union and Russia -- in Jerusalem on Monday morning before leaving for Cairo, a U.S. official told reporters. Expectations for a breakthrough had been low because of the gulf of mistrust between the two sides, sharp differences on key issues and skepticism about U.S. commitment. But after failing to narrow Israel-Palestinian differences, Powell said both sides had pledged to seek an end to hostilities. "Nobody should underestimate the challenges ahead," he said at a joint news conference with Abbas in the West Bank town of Jericho. "Let's not waste another day." Powell called on the revamped Palestinian government to move quickly to disarm Palestinian fighters. But Sharon said the Palestinians could expect nothing more than modest humanitarian gestures from Israel until Abbas's government cracked down on 'militants' spearheading an uprising. Powell said Abbas "made clear to me today he understands the importance of ending 'terrorism'." But the Palestinian premier made no public commitment other than reiterating his opposition to the use of violence "by any party." Abbas instead chided Israel for withholding its full acceptance of the road map and called for troop pullbacks from Palestinian cities which Israeli forces occupied or blockaded in the past year following a spate of bombing attacks. **PHOTO CAPTION*** A foreign construction worker works on unfinished buildings in the Jewish settlement of Alon Svut, one of the settlements of the Gush Etzion block of settlements, in the southern West Bank, Sunday, May 11, 2003. (AP Photo/Oded Balilty)