At a Pentagon news conference, Rumsfeld was asked about a poll that indicated nearly 70 percent of respondents believed the Iraqi leader probably was personally involved.
"I've not seen any indication that would lead me to believe that I could say that," Rumsfeld said.
He added: "We know he was giving $25,000 a family for anyone who would go out and kill innocent men, women and children. And we know of various other activities. But on that specific one, no, not to my knowledge."
The Bush administration has asserted that Saddam's government had links to Al Qaeda (search), the terrorist network led by Usama bin Laden that masterminded the Sept. 11 attacks. And in various public statements over the past year or so administration officials have suggested close links.
Vice President Dick Cheney (search) said on Sunday, for example, that success in stabilizing and democratizing Iraq would strike a major blow at the "the geographic base of the terrorists who have had us under assault for many years, but most especially on 9-11."
And Tuesday, in an interview on ABC's "Nightline," White House National Security Adviser Condoleezza Rice (search) said that one of the reasons President Bush went to war against Saddam was because he posed a threat in "a region from which the 9-11 threat emerged."
In an appearance on NBC's "Meet the Press," Cheney was asked whether he was surprised that more than two-thirds of Americans in the Washington Post poll would express a belief that Iraq was behind the attacks.
"No, I think it's not surprising that people make that connection," he replied.
Rice, asked about the same poll numbers, said, "We have never claimed that Saddam Hussein had either direction or control of 9-11."
"What we have said," she added, "is that this is someone who supported terrorists, helped to train them, but most importantly that this is someone who, with his animus toward the United States, with his penchant for and capability to gain weapons of mass destruction, and his obvious willingness to use them, was a threat in this region that we were not prepared to tolerate."
Cheney said he recalled being asked about an Iraq connection to 9-11 shortly after the attacks, and he recalled saying he knew of no evidence at that point.
"Subsequent to that, we have learned a couple of things," he said. "We learned more and more that there was a relationship between Iraq and Al Qaeda that stretched back through most of the decade of the '90s; that it involved training, for example, on BW (biological warfare) and CW (chemical warfare) -- that Al Qaeda sent personnel to Baghdad to get trained on the systems, and involved the Iraqis providing bomb-making expertise and advice to the Al Qaeda organization."
At his Pentagon news conference, Rumsfeld reiterated his belief that U.S. and coalition forces in Iraq are making satisfactory progress in stabilizing the country.
He said it was an "open question" whether the United States would get the 10,000 to 15,000 additional international troops it seeks to create a third multinational division for security duty in Iraq. The Pentagon has been hopeful of getting at least that many additional troops from Turkey, Pakistan or other friendly countries to beef up security and possibly to allow some of the 130,000 U.S. troops there to go home next year.
"It would relieve some of the pressure on our forces," Rumsfeld said. "Whether or not there will be a (United Nations) resolution and whether or not -- even if there were a resolution -- we would get that number of troops is an open question."
Rice acknowledged that if commitments for more troops are gained, it "could be months" before they were in place.
Gen. Peter Pace, the vice chairman of the Joint Chiefs of Staff who appeared with Rumsfeld, said there are more than 210,000 coalition forces in Iraq: 130,000 American troops, 24,000 British and other international troops, and 60,000 Iraqi police, border guards and civil defense forces.