New York ? President Bush will use a U.N. speech today to demand that Iraq admit weapons inspectors and to urge world leaders to insist on Saddam Hussein’s compliance, U.S. officials said.

Bush intends to cite a list of at least a dozen instances in which the Iraqi president defied U.N. resolutions calling for inspections of suspected weapons sites and for disarmament.

At the same time, Bush hopes to gather support from reluctant allies and others for using force against Iraq. Bush’s strategists, meanwhile, are considering setting a deadline with serious consequences if Saddam balks.

The implicit warning of U.S. military action to remove Saddam from power would come in a U.N. Security Council resolution by Britain. A veto by Russia, China or France would kill the measure.

Bush is “going to make clear that the current regime in Iraq is an outlaw regime, that it has defied U.N. resolutions for 11 years now,” a senior U.S. official said.

Bush’s national security adviser, Condoleezza Rice, has put the matter in stark terms, saying that with Iraq’s buildup of destructive weapons, “We don’t want the smoking gun to be a mushroom cloud.”

Before Bush speaks, U.N. Secretary-General Kofi Annan will call on Iraq to admit weapons inspectors or face any consequences the Security Council decides to impose.

In Annan’s speech, released Wednesday night, he opposes any pre-emptive action without Security Council backing.

“When states decide to use force to deal with broader threats to international peace and security, there is no substitute for the unique legitimacy provided by the United Nations,” Annan’s speech reads.

Bush contends he does not need new legal authority to use force to try to oust Saddam. The White House cites U.N. resolutions dating from 1990-91 Persian Gulf war that reversed Iraq’s annexation of Kuwait.

Britain is solidly in the U.S. camp, but most other foreign leaders have expressed doubts. Bush has said he is prepared to act unilaterally.