It is "highly doubtful" that Saddam Hussein will comply with U.S. demands and avoid a confrontation with the world community, President Bush said Friday morning.

Meeting with African leaders at the United Nations, Bush reiterated his request for a U.N. resolution demanding Saddam end his weapons programs.

"We're talking days and weeks, not months and years," the president said as he outlined his request for a U.N.-imposed deadline on Iraq. "That's essential for the safety of the world."

Bush also wondered aloud why some Democratic lawmakers want to wait until the U.N. passes its measure before acting on a congressional resolution allowing him to act against Iraq.

Chuckling, the president said he could not imagine being an elected member of Congress and saying, "Vote for me and, oh, on matters of national security, I think I'm going to want somebody else to act."

That comment drew responses from a couple senators, including Senate Majority Leader Tom Daschle, D-S.D., who said he hasn't seen enough evidence to justify a pre-emptive attack on Iraq, and Sen. Joseph Biden, D-Del., chairman of the Senate Foreign Relations Committee.

"This should be something done in a very deliberate manner. We should not try to rush history here," Biden told CBS's Early Show.

On Thursday, Bush asked the U.N. to join with the United States in taking action against the "grave and gathering danger" of Saddam Hussein unless the Iraqi president quickly meets a series of demands, including unconditional disarmament and an end to persecution of minorities.

"I am highly doubtful that he will meet our demands. I hope he does, but I'm highly doubtful," Bush told reporters. "The reason I'm doubtful is he's had 11 years to meet the demands. For 11 long years, he has basically told the United Nations and the world he doesn't care."

Iraqi Deputy Prime Minister Tariq Aziz said Friday that Iraq opposes the return of U.N. weapons inspectors and that Bush's speech to the United Nations was "full of lies."

"We do not accept Bush's conditions," Aziz said in an interview in Baghdad Thursday with the Saudi-owned MBC television network and aired Friday.

"The unconditional return of the inspectors will not solve the problem. We have an experience with them (the United States and the British) ... the 1998 experience," Aziz said in reference to U.S. and British attacks launched in 1998 to punish Saddam Hussein's government for not cooperating with U.N. weapons inspections.

White House Press Secretary Ari Fleischer said that Aziz's rejection of the ultimatum suggests that "obviously they have something to hide."

Sen. John Warner, R-Va., ranking member of the Senate Armed Services Committee, added that Iraq is probably alarmed "now that the world is concerned that they do have weapons of mass destruction."

"If any type of inspection team goes back in, the chances are they'll turn up one or two of those caches of those weapons," he said.

Secretary of State Colin Powell began Friday with the task of trying to convince key foreign governments to back a tough U.N. resolution.

Of the five permanent members of the U.N. Security Council, each of which has veto power, only the United States and Britain currently favor a hard line against Saddam.

Powell's job is to get the other three -- Russia, China and France -- to agree to a resolution that Iraq must re-admit weapons inspectors or face likely military action.

Under Secretary of State John Bolton said from Moscow that he was "very confident" that the U.S. and Russian presidents could reach an agreement on this crisis.

To add heft to Powell's meetings, the administration was planning to send Vice President Dick Cheney to a meeting of the General Assembly session.

Powell told the morning news shows that the key to successful multilateral pressure on Iraq would be putting up a deadline

On ABC's Good Morning America, he said, "There have to be deadlines this time. In the absence of deadlines, the Iraqis will string us out, will try to negotiate away or simply ignore the resolution."

Powell stressed on Friday, however, that Bush has not yet made a decision about whether to use military force.

"The president has made it clear that he feels Saddam Hussein and the Iraqi regime to be abhorrent," he said on CBS, "but he's not declaring war on anybody at this point."

Representatives of other nations likely will take the weekend to consult with leaders back home before agreeing to a new resolution, he said.

"But I don't want to put a time dimension on it right now because I think it's something for me and my colleagues in the Security Council to work out," Powell said.

After 16 U.N. resolutions on Iraq demanding weapons inspection and disarmament since the Persian Gulf war of 1990-91, Saddam should know his obligations, a senior U.S. official said, adding that there will be no negotiations with Iraq.

"It's not as if Saddam Hussein doesn't know what he is supposed to do. So we don't expect the process of coming to a resolution to take months," the official said.

Nor, the official said, will the United States wait months for Iraq to comply with any new U.N. demands.

The Associated Press contributed to this report.