The U.N. Security Council failed to agree on a statement late on Wednesday condemning a deadly Israeli attack on a U.N. observer post in Lebanon after the United States blocked language that appeared critical of Israel.

United Nations Secretary General Kofi Annan seen here 24 July 2006 at UN headquarters in New York. Asked about Annan's statement suggesting Israel had targeted the outpost, Canadian PM Stephen Harper said: "I certainly doubt that to be the case." [AFP]

During a daylong debate, council members made numerous changes to a text put forward by China, which lost one of the four officers killed in the attack.

Their patience ran out when Washington demanded the deletion of language condemning "any deliberate attack against U.N. personnel."

Qatar, the council's sole Arab member, then said it needed time to consult with its government overnight, and the deliberations adjourned until Thursday morning. A policy statement needs the approval of all 15 council members.

China's U.N. ambassador, Wang Guangya, called for a strong statement of condemnation after an Israeli air attack destroyed the U.N. post in southern Lebanon on Tuesday, killing peacekeepers from Austria, Canada, China and Finland.

The attack prompted U.N. Secretary-General Kofi Annan to ask Israel to investigate what he termed the "apparently deliberate targeting" of the U.N. observer post.

Israeli Prime Minister Ehud Olmert, while expressing "deep sorrow" over the deaths and agreeing to an investigation, voiced shock at the suggestion the attack was deliberate.

Wang acknowledged it was important to preserve council unity but said the council had to show its concern for the safety of U.N. peacekeepers.

Asked whether the U.S. position might affect China's attitude toward American efforts for a resolution on Iran's nuclear program, now under negotiation, Wang indicated there might be some spillover.

"I think that all members will reflect, on what lessons, if there are any, (can be) learned from this episode," Wang said.

China's initial draft called for an immediate end to the fighting in Lebanon and referred to the "apparently deliberate targeting" of the U.N. troops by Israel.

U.S. Ambassador John Bolton said there was no evidence the attack was deliberate, and Wang agreed to take out the two phrases at a very early stage.

Hours later, U.S. envoy Molly Phee said the United States wanted language deleted expressing the council's condemnation of "any deliberate attack against U.N. personnel."

Phee filled in for Bolton who was in Washington preparing for a Senate confirmation hearing on Thursday on his nomination as U.N. ambassador.