Republican presidential candidate Fred Thompson on Friday criticized rival Mike Huckabee, saying it was "surprising" a presidential candidate wouldn't know about a newly released intelligence report that said Iran suspended its nuclear weapons program in 2003.

"For a presidential candidate not to know that or not to keep up with that I think is very surprising," Thompson said. Huckabee, a former Arkansas governor, told reporters earlier this week he was not aware of the National Intelligence Estimate report on Iran.

Thompson's comments come at a time when the latest Associated Press-Ipsos poll shows Huckabee's stock rising while support for the former U.S. senator from Tennessee is falling.

Thompson named Iran as the country's biggest long-term threat, saying "they've been killing our people for years" through Islamic terrorist groups like Hezbollah and Hamas, and would be "willing to sacrifice millions of lives" in challenging the United States.

Despite the intelligence report's findings, Thompson said, Iran has "given every indication they're developing nuclear capability."

Thompson described himself in remarks to supporters at Ohio Republican Party headquarters as a solid conservative candidate who will not waver or change his positions to win political office.

In brief remarks to supporters at Ohio Republican Party headquarters, the actor alluded to fellow Republican candidate Mitt Romney without naming him.

"Where we stand on the issues doesn't depend on where we're standing and what political office we're running for," Thompson said, trying to stand out in a race where recent polls have showed his support dropping. Romney, the former governor of Massachusetts, has received criticism for changing his position on a number of issues, including abortion.

Thompson emerged in the race with high hopes that he could win over a dissatisfied conservative GOP core. But his candidacy has failed to catch on in the way many expected it would. Upstart Huckabee, who has lit a fire under social conservatives, has started to erode Thompson's support, picking up roughly the same ground in a recent poll that Thompson has lost.

Thompson spoke Friday to some of the criticism his campaign has received, comparing what pundits are saying now to what happened when he won his U.S. Senate seat in Tennessee in 1994 after trailing the incumbent by 20 points in the polls.

"Everybody says we started too late, everybody says he didn't really have the fire in the belly, everybody says he's not raising enough money," Thompson said. "Election night we were 20 points ahead."

Thompson said his administration would emphasize the Republican mantra of a strong national defense, low taxes and reduced regulation, but his comments were largely devoid of specifics.

He said the country was at a crossroads where it could either choose to continue the path it has been on for more than 200 years, or it could turn into a European-like welfare state with a weak national defense.