President Bush's insistence that the United States is prepared to take military action, if necessary, to force Iraq to disarm has provoked questions in Washington about whether the United States is taking too unilateral an approach.

The issue was raised during the U.S. congressional debate that preceded last week's vote authorizing the president to use force against Iraq, if necessary, with or without U.N. support.

The resolution passed by wide margins in both the House and Senate, despite concerns by many Democrats. The resolution encouraged the president to exhaust all diplomatic means first.

President Bush said he has not yet decided whether to use force, but he said he is ready to lead a coalition against Iraq, if the international community fails to act to disarm Saddam Hussein. "The choice is up to the United Nations to show its resolve. The choice is up to Saddam Hussein to fulfill his word. If neither of them acts, the United States in deliberate fashion will lead a coalition to take away the world's worst weapons from one of the world's worst leaders," Mr. Bush said.

Many Democrats in Congress, however, wanted the Bush administration to emphasize a multilateral approach. Nearly half the Democrats in the Senate voted against authorizing force, and in the House a majority of Democrats opposed it.

Democratic Senator Carl Levin of Michigan had introduced a resolution that called for a broader role for the United Nations. The Levin resolution, which was defeated, would have authorized military action in connection with a new U.N. Security Council resolution, but would have deferred a decision if the United Nations did not act. Senator Levin warned against what he called a "go it alone strategy."

"At the time when we are seeking U.N. support, we would send the wrong message to the United Nations. Telling the United Nations that 'if you do not enforce your resolutions, we will,' not only sends an inconsistent message, it lets the U.N. off the hook. We should be seeking to unite the world against Saddam Hussein, not divide it," Mr. Levin said.

Senator Paul Wellstone, a Minnesota Democrat, agreed with Senator Levin on the need for a multilateral approach. "Only a broad coalition of nations, united to disarm Saddam, while preserving our war on terror, can succeed. Our response will be far more effective, if Saddam sees the whole world arrayed against him," Mr. Wellstone said.

Republicans, on the other hand, overwhelmingly supported the resolution authorizing the use of force. Senator Jim Bunning of Kentucky argued that the United States should work with its allies and the United Nations, but in a way that preserves the nation's right to act in self-defense.

Senator Rick Santorum, a Republican from Pennsylvania, told CBS television that the United States has to act, if the United Nations does not. "Saddam Hussein has broken U.N. resolutions, and for the United Nations to be a relevant organization, they have to enforce the resolutions. If they're not willing to enforce the resolutions to maintain peace in the region and stability for the world, then, I think, we have an obligation to go ahead and move forward. And we have, as you've seen already, support from allies around the globe in this mission," he said.

While members of Congress disagreed about whether to emphasize a unilateral or multilateral approach, there is broad agreement of the need to act, whether through military or diplomatic means, to force Iraq to disarm. And at the U.N., the Bush administration continues to push for a resolution demanding that Iraq give up weapons of mass destruction and threatening force if it fails to comply.