Secretary of State Colin Powell (search) asked Syria on Friday to help stem terrorism in the Middle East.

Powell telephoned the request to Foreign Minister Farouk al-Sharaa as he widened his appeal to Arab countries.

Syria, itself, is listed by the State Department (search) as a sponsor of terror. Spokesman Richard Boucher said Hamas and other groups had offices in Damascus.

Powell on Thursday made similar appeals to the foreign ministers of Egypt, Jordan and Saudi Arabia.

In all the conversations, including the one with the Syrian minister, Powell's message was "to stop the violence, to stop the violent groups," Boucher said.

"I think it is clear what we want," Powell said Friday. "Hamas to stop it. Palestinian Islamic Jihad, al-Aqsa Brigades, all of them to stop it."

"We have to get moving and bring the terror down," he said.

On the Israeli side, Powell said "we all are anxious to see restraint."

But he said "we understand that it's important to get the terror down" and if that happens "the response to terror will no longer be required."

Meanwhile, 31 Democrats in the House wrote President Bush saying they were "deeply dismayed" by the president's criticism of Israel after it tried to assassinate a Hamas leader.

"The attack on Hamas leader Abdel Rantisi was clearly justified as an application of Israel's right to self-defense," the letter said. "Indeed, just as the United States has the right to prosecute the war on terrorism, Israel has the same right to fight terrorism in its own neighborhood and its own capital."

The letter said Rantisi's public statements "serve as instructions for terrorists to carry out attacks." It quoted Rantisi as calling for strikes against the 'Zionist enemy' in order to expel Israelis and "not leave one Jew in Palestine."

Assistant Secretary of State John S. Wolf will arrive in the area this weekend to try to spur Israel and the Palestinians into peacemaking moves, Boucher said.

Wolf will head a group of State Department and CIA officials whose assignment is to help mediate between the two sides and to assist in strengthening security.

They will start meeting with Israeli and Palestinian officials shortly after their arrival, the spokesman said.

Asked about a pause Friday in the bloodletting, Boucher said, "I don't think we count it in hours."

White House spokesman Ari Fleischer said, meanwhile, that "Wolf's mission is to help the parties even in the darkest moments find their way to remember the vision to peace."

President Bush expects them to help both sides implement the road map, "knowing that there will be violence that interrupts progress on the way toward implementing the actions that both parties are supposed to take," Fleischer said.

U.N. Secretary-General Kofi Annan (search) has suggested positioning an armed force as a buffer between Israel and the Palestinians.

Boucher, in response, said third parties could help but it was mostly up to Israel and the Palestinians to stem the violence.

"It is an idea that comes up again and again," he said. "Frankly, we've heard people talk about it the last 10 or 15 years. But, again and again when it's come up, I think people who have looked at it closely have always said, absent the agreement of the parties, the interpositional force can't achieve its own goals without the parties agreeing to do certain things."

At the same time, Boucher said the Bush administration had urged the European Union to designate the political arm of Hamas as a terror group.

The State Department makes no distinction between political and military parts of such groups in designating them as terrorists.

Zalman Shoval, an adviser to Israeli Prime Minister Ariel Sharon, said, meanwhile, that the road map would not survive unless there was "some sort of cease-fire and absolute end to terror."

Otherwise, Shoval said, "this whole thing might be an exercise in futility."

But Shoval, in his appearance before the Hudson Institute, a private research group, said, "Israel is not going to be a spoiler as long as there is a reasonable chance of progress."