The fissure in the U.N. Security Council deepened Thursday when France rejected a British compromise on Iraq, infuriating London and prompting the United States to consider postponing a vote on an ultimatum against Baghdad until next week.

Iraq, reveling in the turmoil at the council, dismissed Britain's plan, which lists six disarmament requirements Baghdad would have to meet or else face "serious consequences."

Britain proposed the list in a bid to win votes on the council for a U.S.-backed resolution authorizing war unless Baghdad meets a deadline. To sweeten the offer, British officials also suggested pushing back the deadline from Monday, as originally proposed by the United States.

France's flat rejection of the proposals clearly angered British leaders. Foreign Secretary Jack Straw called the French attitude "extraordinary."

Prime Minister Tony Blair feels the French "have become completely intransigent and have literally threatened to veto almost anything that is put forward to the U.N. Security Council," Conservative Party leader Iain Duncan Smith said after meeting with Blair in London.

Blair's spokesman said talks at the United Nations would continue though the weekend as Britain works "flat out" to win a U.N. resolution authorizing war. Germany also rejected the British proposals, and Russia and China were skeptical.

The United States had been hoping for a vote this week, but the White House announced Thursday that President Bush was willing to put it off until next week if that would help gain support.

"It may conclude tomorrow. It may continue into next week," White House spokesman Ari Fleischer said. White House officials said the administration was scrambling to organize a European trip for Bush. Later, however, those officials and others said the planning had been stopped and Bush did not intend to leave Washington.

U.N. Secretary-General Kofi Annan on Thursday raised the possibility of a summit of a group of interested world leaders who are "searching for a compromise to get us out of this crisis." He said such a summit, with leaders not necessarily on the Security Council, was suggested by Brazil.

Postponing a vote would likely mean pushing back the Monday deadline that the United States had sought. During tough negotiations in recent days, U.S. officials gave conflicting statements on whether Washington would be willing to wait on a vote.

But Britain -- Bush's strongest supporter for military action -- is desperate to get a U.N. resolution approving war to avert an uproar at home. The British leader could face a revolt from members of his own Labor Party if he joins the United States in unilaterally launching war.

Duncan Smith, the opposition leader, said Thursday that Blair believes a new resolution on Iraq is "now less likely than at any time" and that French obstinance brings the likelihood of war closer.

France and Germany rejected the British proposals because they would still set a deadline for war.

"It's not about giving a few more days to Iraq before resorting to force but about resolutely advancing through peaceful disarmament," French Foreign Minister Dominique de Villepin said in a statement.

In Berlin, Chancellor Gerhard Schroeder's national security adviser, Bernd Muetzelburg, said the British proposal still "basically gives an authorization for war" -- an approach, he said, that "probably will not lead to a success."

China's U.N. Ambassador Wang Yingfan said he doubted the British compromise could "lead to consensus." Russia's U.N. Ambassador Sergey Lavrov said his government would study the proposal "but we see automaticity (of military action) still there."

The Security Council scheduled another meeting for Thursday afternoon to discuss the proposal.

Britain presented the plan Wednesday as a "trial balloon," said British Ambassador Jeremy Greenstock. The six requirements it lays out for Baghdad include the destruction of suspected mobile weapons labs and a television appearance by Saddam renouncing his efforts to develop biological, chemical and nuclear weapons.

The United States had not fully backed the changes, waiting to gauge reaction. If council members rallied behind it, U.S. Ambassador John Negroponte had said Washington would be willing to accept "a very, very, very brief extension" of the Monday deadline.

Iraq's foreign minister, Naji Sabri, dismissed the British proposal as "an attempt to beautify a rejected aggressive project."

Britain "is trying to polish this project, which has been rejected by the majority of Security Council members," Sabri told reporters in Baghdad. "The United States, with its policy of aggression, wants international cover for this aggression."

U.S. officials insisted they were making progress in picking up votes on the council.

Based on public statements and private interviews with senior diplomats, The Associated Press has determined that the resolution has support from seven countries: Britain, the United States, Spain, Bulgaria, Cameroon, Pakistan and Mexico.

Angola and Guinea were still uncommitted. Chile, Germany and China are expected to abstain. Russia could also abstain or vote against the draft along with Syria and France.

The United States needs nine votes, and no veto, for the resolution to pass.