British Prime Minister Tony Blair says he expects the United Nations will authorize military force against Iraq if Baghdad violates a disarmament resolution. But the prime minister says he would not put an arbitrary deadline on the U.N. weapons inspections.

Mr. Blair said he has little doubt the U.N. Security Council will support a war on Iraq if Saddam Hussein is found to be hiding weapons of mass destruction.

"My own judgment - and I have spoken to the key players involved in this - my own judgment is that if there is a breach, then action will be authorized," Mr. Blair said.

The prime minister spoke as a new public opinion poll found that nearly three out of five Britons would oppose a war unless the United Nations sanctioned it.

Mr. Blair said the only way he sees a war happening without U.N. backing is if some country on the Security Council threatened to veto military action.

The prime minister said the best way to avoid war is for Saddam Hussein to work with U.N. weapons inspectors.

"It is not a conflict that is inevitable, but disarmament is inevitable," he said, "and what Saddam has to do is cooperate fully with the weapons inspectors in saying what weapons he has, in cooperating with them in destroying those weapons."

Mr. Blair said January 27 would be an important date, because U.N. weapons inspectors will make a report then to the Security Council. But he said there are no "arbitrary time frames" on when the inspectors must finish their work in Iraq.

U.N. spokesman Mark Gwozdecky of the International Atomic Energy Agency says the inspectors could take one year to complete "a credible inspection process."

Meanwhile, the United States and Britain are sending troops, ships and planes to the Persian Gulf area to put pressure on Saddam Hussein. For security reasons, Mr. Blair refused to answer any questions about how long British forces might stay in the region.