PORT ST. LUCIE, Fla. — Newt Gingrich turned aggressive against Mitt Romney at a brief news conference here Saturday morning.

Gingrich blasted Romney as "dishonest" for his performance at the final televised debate Thursday night. Asked if he was happy with his own showing, Gingrich replied "No," but then added: "You cannot debate someone who's dishonest. You just can't. People say I'm a good debater. I can't debate somebody who won't tell the truth."


As evidence of this charge, he pointed to Romney's explanation of why he voted for Paul Tsongas in the 1992 Democratic primary in Massachusetts. Romney said that he had never voted for a Democrat when a Republican was on the ballot.

There was a Republican primary in Massachusetts on the same day in 1992, with sitting president George H. Bush competing against Pat Buchanan.The Romney camp has said that this contest was essentially meaningless but Gingrich insisted otherwise.

"There is no practical way in a civil debate to deal with somebody who is willing to say something that is just totally dishonest," Gingrich said. "So I didn't like either debate. A couple of times I am staring in amazement. I know what he's saying is untrue."

The two televised Florida debates held earlier this week were potentially decisive in stopping the momentum that Gingrich had carried from his South Carolina primary victory. Several polls in recent days have shown Romney with a significant lead here.

Gingrich's assault on Romney's integrity struck the same tone as a new TV ad released by his campaign Friday, which used old footage of former Arkansas Gov. Mike Huckabee appearing to describe Romney as "dishonest." Huckabee has disassociated himself from the Gingrich ad. But at his event here, Gingrich insisted that the clip was taken from "an anti-Romney ad" that Huckabee had run during the 2008 primary race. "I'd be happy to run the whole Huckabee commercial," Gingrich added.

Gingrich had steered clear of harsh attacks on Romney in his most recent events. But — even though the next move of the mercurial Gingrich is always hard to predict — the latest charges of dishonesty seemed to indicate that he was returning to a more bare-knuckle style with only three full days of campaigning left before Tuesday's primary.