The Bush administration on Sunday urged Israelis to avoid civilian casualties in the fighting in Lebanon and expressed sorrow about the deaths of at least 56 civilians in a village in southern Lebanon.

But the White House reaffirmed the administration's insistence on reaching a sustainable cease-fire. "The key here is that we want a cease-fire that will work," press secretary Tony Snow told reporters. President Bush was told before 7 a.m. about the attack on Qana and had spoken with Secretary of State Condoleezza Rice, who was in Jerusalem.

The administration offered condolences to those killed when Israeli missiles hit several buildings as people slept.

"This was a terrible and tragic incident," spokesman Blair Jones said. "We continue to urge the Israeli government to exercise the utmost care so as to avoid any civilian casualties. This tragic incident shows why this is so critical."

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The State Department's third-ranking official reaffirmed the White House's position that Israel has the right to defend itself and contended an agreement was near on ending the fighting that has ravaged Lebanon.

Undersecretary of State Nicholas Burns expressed optimism despite the airstrike. After the attack, Rice canceled a visit to meet with Lebanon's prime minister and, according to a U.S. official, decided to meet with the Israeli prime minister before leaving Jerusalem and returning to Washington on Monday.

Burns said the U.S. was committed to securing a cease-fire between Israelis and Hezbollah militants in Lebanon, focusing on a multinational force in the region. Snow said talks at the United Nations about troop contributions would not begin until Tuesday or Wednesday.

"This is a very sad day. We are working toward that cease-fire," Burns said. "We are close to a political agreement between Israel and Lebanon to end this fighting."

Yet he endorsed Israel's military objectives, saying "This has not been a good 2 1/2 weeks for Hezbollah from a military point of view, and they've got to be worried about continued Israeli offensive operations."

The administration has insisted that any cease-fire come with conditions to address long-standing regional disputes, including the insistence by Israel that Hezbollah be disarmed -- something the Lebanese government has been unable to do.

"We want to avoid a situation where we essentially put a Band-Aid on something," Burns said. "We have to a have view of a sustainable cease-fire. We have to make sure Hezbollah is not allowed to be in a position to strike again."

The fighting was triggered by Hezbollah's cross-border raid from Lebanon into Israel and the capture of two Israeli soldiers.

President Bush has said Israel has a right to defend itself and that "every nation must defend herself against terrorist attacks and the killing of innocent life."

Burns did not deviate from that position. "The United States believes, and all countries believe, that Israel has a right to self-defense. Israel was attacked two weeks ago. It was Hezbollah who started this and crossed the blue-line," he said.

Burns appeared on ABC's "This Week" and "FOX News Sunday."

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