The Bush administration has made clear that it expects to be at war with Iraq within the next several weeks. But senior officials acknowledge they have yet to determine how to get there with the least amount of damage to its international relations and the largest possible number of allies on the front lines.

Much is riding on the assessment of Iraqi cooperation with United Nations weapons inspections that chief inspector Hans Blix will deliver to the Security Council on Friday. If Blix declares that Iraq has utterly failed to comply with the demands of last November's council resolution, as the administration is pressing him to do, U.S. officials see a relatively simple path forward.

The United States and its chief Security Council ally Britain will call for the council to vote to impose the "serious consequences" -- meaning a military attack on Iraq -- that it promised to consider when it unanimously passed Resolution 1441.

But in the likely event that Blix's report will present a less black and white picture, saying that Iraq has failed to cooperate in many important ways but that some progress has been made, the administration faces the strong possibility of having to fight a war that the United Nations has refused to approve. Security Council members France, Russia and China -- each with the power to veto a new resolution -- and the chamber's current president, Germany, already have called for giving inspections more time.

The stakes for Friday's meeting increased yesterday when all four opponents announced their foreign ministers would attend. U.S. officials said Secretary of State Colin L. Powell likely would be going as well.

Russian Foreign Minister Igor Ivanov denied that their joint stance was "a challenge thrown down to America." But U.S. action outside the United Nations, he said, "would create a schism in the international community."

U.S. and British officials have drafted several possible resolutions, sent strategy documents flying back and forth across the Atlantic and begun cajoling and twisting the arms of fence-sitters among the rest of the council's 15 members. But they have come to no decision on "how you get from A to B -- from where we are now to a Security Council resolution that effectively authorizes the use of force," a senior official closely involved in the deliberations said. "We don't have an answer to that now."

Pending the perceived strength or weakness of Blix's presentation, the official said, "we have not yet come to a firm view, and are having to build in all kinds of tactical flexibility. . . . We are agreed that action should follow pretty fast after February 14, but we've got to be nimble and flexible."

Senior U.S. and diplomatic sources said the options under discussion include going for broke and daring opponents to veto an authorization for war. "If the United States and Britain and other friends in Europe continue to be implacable on this, people in places like Paris and Berlin are going to have to start thinking what side they want to be on," said one diplomat. "A veto of a resolution is a hugely significant thing to do which will echo around the world for years."

Another option is to introduce a new measure invoking the words of Resolution 1441, which says that "failure by Iraq at any time to comply with, and cooperate fully in the implementation of, this resolution shall constitute a further material breach of Iraq's obligations." Since "no one in their right mind is going to give the Iraqis a clean bill of health," the diplomat said, it would be hard to argue that the breach has not already occurred. Declaring such a judgment is implicit authorization, the United States, Britain and their allies then would proceed to war.

Arab leaders have been pushing for a resolution giving Iraqi President Saddam Hussein an ultimatum, with a short deadline to either "shape up, get out, or face the consequences," the diplomat said. Powell said in congressional testimony yesterday that the United States is now discussing the possibility of exile for Hussein and his top officials with other governments.

With 150,000 U.S. troops deployed to the Persian Gulf region and opinion polls showing most Americans believe that war is the best option, the need to try to persuade international organizations has been frustrating for an administration that came to office with little regard for multinational consensus.

At NATO, where all decisions must be unanimous, senior officials this week have attempted to declare a new standard for at least symbolic victory. Although three of the alliance's 19 members -- France, Germany and Belgium -- have blocked agreement on defensive measures to protect Turkey in the event of a war, Defense Secretary Donald H. Rumsfeld has emphasized that the United States has a majority of NATO members on its side.

In NATO and the United Nations, the administration has portrayed the battle as what a senior U.S. official called "a split within Europe, among the Europeans," that has little to do with U.S.-European relations. "It's all a very complicated piece of theater with many layers," he said

Along with the three European members of the U.N. Security Council that back the U.S. position -- Britain, Spain and Bulgaria -- the administration believes it can pressure most other members from Africa, Latin America and Africa to agree to a new resolution. Even if a veto is threatened, it sees a simple majority as the moral equivalent of passage.

U.S. officials have said repeatedly that full U.N. authority already exists to declare war on Iraq and no further resolution is necessary. But there are compelling reasons at least to try to achieve some form of U.N. acquiescence, even if it does not amount to a full mandate for war. Both Britain and Spain, the second-most important U.S. ally on the Security Council in the Iraq debate, are desperate for international cover that would avoid the image of them acting as U.S. subalterns.

At the very least, a senior administration official said, British Prime Minister Tony Blair "is saying he'd rather try, and fail, than not try" for a new resolution.

Officials insisted that the most obstinate opponents have left room for a change of heart, although they acknowledge having to dig deep to find it. Despite strong statements that there is no current justification for war, Russian President Vladimir Putin "is not going to get himself locked in," the senior official said. "He was very careful to talk about 'no unjustified use of force'; he's not taking an unalterable stand against the use of force. He's leaving himself some wiggle room."

"The French," the official added, "have also left themselves some wiggle room. They've never said no war under any circumstances." German Chancellor Gerhard Schroeder "is the only one who's boxed himself in, and he doesn't have a veto."

"I'm not saying it's going to be a walk," the official continued. "I'm not calmly predicting that we've got them just where we want them. It's tough stuff. But the Germans and the French are kidding themselves if they think that a [negative] Blix report and Iraq's actual actions" in failing to offer full cooperation "make no difference."

At the al-Mutanna military site north of Baghdad, U.N. weapons inspectors work behind Iraqi soldiers to destroy containers filled with mustard gas.