President Bush (search) declined to criticize Israel Monday for its air strike deep inside Syria, saying Israel "has got a right to defend herself." But Bush also said he had cautioned Israeli Prime Minister Ariel Sharon (search) to try to avoid escalating tensions in the region.

Bush decried the "needless murder" of 19 people in a suicide attack by a Palestinian militant group in Israel on Saturday that led to the Israeli attack on a suspected terrorist camp in Syria.

Bush said that the Palestinian Authority must do more to fight terror and "must use whatever means is necessary .... All parties must assume responsibility."

Bush commented after the new Palestinian prime minister, Ahmed Qureia (search), said he hopes to negotiate a quick truce with Israel, but won't use force against Palestinian militants under any circumstances -- despite U.S. demands for a clampdown on armed groups.

The president was asked if he could work with a prime minister who would not use force against militants.

"We have not changed. Parties need to assume responsibility for their actions. In order for there to be a Palestinian state, the Palestinian Authority must fight terror and must use whatever means is necessary to fight terror," he replied.

During a White House news conference with Kenyan President Mwai Kibaki, Bush said that he had spoken with Sharon on Sunday.

"I made it very clear to the prime minister that...Israel's got a right to defend herself, that Israel must not feel constrained in terms of defending the homeland."

However, Bush added, "I said that it's very important that any action Israel takes should avoid escalation and creating higher tensions."

Israeli warplanes on Sunday bombed a suspected terrorist camp northwest of Damascus in retaliation for the suicide bombing the day before at a seaside restaurant in Haifa.

The Islamic Jihad claimed responsibility for the bombing but denied having training bases in Syria.

Earlier, White House spokesman Scott McClellan called the suicide bombing "despicable" but declined to weigh in on whether the suspected training camp was an appropriate targets for retaliation.

He would not say whether the United States agreed with Israel's contention that the site was a training camp for terrorists, nor would he say whether the Bush administration would veto a U.N. resolution condemning Israel's airstrike.

"We've always stated that Israel has the right to defend herself," McClellan said, while cautioning the Israeli government to consider the "consequences" of its actions on the peace process.

The U.S.-backed "road map" to Mideast peace has suffered a series of setbacks in recent months, with Israel building homes in new West Bank settlements in defiance of the plan and steady bombings by Palestinians.

"We always pointed out that there would be difficulties along the way," McClellan said.

At the State Department, spokesman Richard Boucher said the Syrian Foreign Ministry hosted a meeting in Damascus of representatives of the permanent five members of the U.N. Security Council.

The Syrians expressed their views, Boucher said, adding that the American representative at the meeting, Gene Cretz, "expressed our views right back."

Boucher said the United States has seen Syria "as a state sponsor of terrorism for a long time.

"We've repeatedly made known our grave concerns about Syrian support for terrorist groups, including Palestinian groups, that are engaged in planning and directing terrorist action against Israel from Syrian territory. That remains our position," he said.

"We have urged all parties to avoid actions that would heighten tensions in the region and to carefully consider the consequences of their actions," he said.

As for the Syrian resolution at the U.N. Security Council condemning the Israeli attack, Boucher said the administration "doesn't think a resolution that deals with only part of the situation and that doesn't make any reference to the terrible and horrible attacks that occurred in Haifa on Saturday is appropriate at this time."

Administration officials said Israel had not informed Washington in advance of its retaliatory strike nor indicated whether it intended any move against Palestinian leader Yasser Arafat to remove him from his West Bank headquarters.

"They don't ask for it and we don't give those," McClellan said.