Secretary of State Colin Powell says any new U.N. Security Council resolution on Iraq must spell out the consequences for the regime of Saddam Hussein if it fails to disarm. In congressional testimony Thursday, Mr. Powell also urged lawmakers to act quickly on a measure backing the use of force by the United States if needed to get Iraqi compliance.

Mr. Powell says the notion advanced by some Security Council members to send weapons inspectors back to Iraq without a new resolution or new powers is a "recipe for failure" that the United States will not support.

Appearing before the House International Relations Committee, the secretary said if inspectors do go back in, it should be without any conditions and with a clear understanding of what would happen if there is further defiance of the U.N.

"This must be an essential element of any road going forward, any plan to go forward from the Security Council," he said. "We must determine what consequences this time will flow from Iraq's failure to take action. That is what makes this different. This time, unlike any time over the previous 12 years of Iraqi defiance, there must be hard consequences. This time, Iraq must comply with the U.N. mandate or there will be decisive action to compel compliance."

Mr. Powell urged immediate action on a congressional resolution authorizing President Bush to use force if necessary to prompt Iraq to disarm. He said it would show the world that Americans are united, and give a "powerful signal" of support for U.S. diplomatic efforts at the United Nations. He also stressed the administration wants to hold out the option of unilateral action if the U.N. fails to act.

"President Bush is hoping that the U.N. will act in a decisive way," he said. "But at the same time, as he has made clear and as our other colleagues in the administration have made clear, and I make clear today, if the United Nations is not able to act and act decisively, and I think that would be a terrible indictment of the U.N., then the United States will have to make its own decision as to whether the danger posed by Iraq is such that we have to act in order to defend our country and to defend our interests."

Mr. Powell's appearance capped a full day of expert testimony in the key House committee on how to deal with Iraq.

Former Clinton administration official Jessica Matthews, now head of Carnegie Endowment for International Peace, proposed that weapons inspectors sent to Iraq be backed up by a heavily armed international force that would insure that inspectors get to see what they want.

But she said for such an approach to work, the United States would have to foreswear military action on "regime change" in Iraq as long as the inspectors were being allowed to do their work.

"The United States has to walk, in policy, a very fine line here," she said. "It must first convince Iraq and other countries that if it does not comply, we will use force. I think we're close to having conveyed that message, certainly to other countries if not to Saddam Hussein, but we are close. But secondly and equally important, we have to convey the message that if Iraq does comply with inspections, we will not [use force]."

However another witness, former CIA Director James Woolsey told the panel Ms. Matthews' idea of so-called "coercive inspections" is probably unworkable because it would require Saddam Hussein to accept the indefinite presence of a foreign armed force.

"We should not be under any illusion that we would be able to have some solution to this problem and then leave," he said. "So I believe what one is talking about for any really effective way of ridding Iraq of weapons of mass destruction and ballistic missiles of greater than 150 kilometers range is an occupying force of very substantial size and a fundamental change in the nature of Iraqi regime. That Iraq would agree to that, I find unimaginable."

Mr. Woolsey said Saddam Hussein may be close to having a nuclear capability and that it is too risky to allow the status quo in Iraq to continue for more than a few more months.

Most committee members said they would support a resolution authorizing military action against Iraq. However Texas Republican Ron Paul said there is no firm evidence Saddam Hussein has nuclear weapons and he warned that military action would further inflame the Muslim world against the United States.

"We're willing to go to war over phantom weapons," he said. "And I think we're falling into a serious trap. And the trap is that we are going to look like we support the Christian west against the Muslim east, which they've been arguing all along. Twenty Arab nations have condemned this proposal to go to war. And I think this is going to turn out to be a monstrous mistake."

Bush administration officials say they hope to get a Congressional resolution on Iraq, early next month before Congress breaks to campaign for the November 5 elections.