National security adviser Condoleezza Rice (search) on Sunday defended her characterization of Saddam Hussein 's nuclear capabilities in the months before the Iraq invasion, even as a published report said government experts had cast doubt at the time.

In the run-up to the March 2003 war, Rice said in a television interview in 2002 that the Iraqi president was trying to obtain high-strength aluminum tubes to rebuild his nuclear weapons program. The tubes, she said, were "only really suited for nuclear weapons programs."

On Sunday, Rice acknowledged she was aware of a debate within the U.S. intelligence community about whether the tubes were intended for nuclear weapons. "I knew that there was a dispute. I actually didn't really know the nature of the dispute," Rice told ABC's "This Week" program.

"The intelligence community assessment as a whole was that these (tubes) were likely and certainly suitable for, and likely for, his nuclear weapons program," Rice said. She said the director of the CIA at the time, George Tenet (search), believed that the tubes were for centrifuge parts.

"When you are faced with an assessment that Saddam Hussein is reconstituting his nuclear weapons program, that he has by the end of the decade the probability of having a nuclear weapon ... the tendency is always not to want to underestimate these programs," Rice said.

But two years later, Rice insisted she has no regrets about how the administration portrayed what it believed was a dangerous threat posed by Saddam.

"I stand by to this day the correctness of the decision to take seriously an intelligence assessment that Saddam Hussein would likely have a nuclear weapon by the end of the decade" if action wasn't taken.

"We were all unhappy that the intelligence was not as good as we had thought that it was. But the essential judgment was absolutely right. Saddam Hussein (search) was a threat," she said.

Later, in another interview, Rice said, "If you underestimate the nuclear threat of a tyrant, you make a really big mistake."

A New York Times story Sunday quoted four CIA officials and a senior administration official as saying that Rice's staff had been told in 2001 that Energy Department (search) experts believed the tubes were probably intended for small artillery rockets — and not nuclear weapons.

Rice said she learned of objections by the Energy Department only after making her 2002 comments.

During an interview in 2002, Rice said the tubes were "only really suited for nuclear weapons programs." In bolstering the administration's argument of the threat the nation faced, she added: "We don't want the smoking gun to be a mushroom cloud."

The Kerry campaign said the latest debate over flawed prewar intelligence only furthers its contention that the administration misled the country into invading Iraq.

"What the Times article is saying is that the top nuclear experts in the country said those aluminum tubes were not for nuclear weapons, and that this was suppressed by the administration, particularly Vice President Cheney," said Kerry foreign policy adviser and former U.N. Ambassador Richard Holbrooke (search).