Fox News host Megyn Kelly on Monday invited Rep. Joe Wilson (R-SC), who shouted "You lie!" at President Barack Obama during his 2009 speech to Congress about health care, to comment on whether it was appropriate to call Republican presidential nominee Mitt Romney a liar.

Kelly pointed out that several Democrats -- like senior Obama adviser David Axelrod and Philadelphia Mayor Michael Nutter -- had accused Romney of being dishonest about his health care plan and tax cuts for the wealthy during the first presidential debate.

"Do you think they are applying a different standard to Gov. Romney than that they demanded of you?" the Fox News host asked Wilson.

"Absolutely, Megan," the congressman replied. "What I did, it was a spontaneous town-hall moment."

"Do they have a defense to this 'liar, liar, liar' theme because they are not doing it on the floor of the U.S. House?" Kelly wondered.

"Indeed on the House floor, it was inappropriate," Wilson admitted. "But, truly, I think it's inexcusable for the highest levels [of the Obama campaign], [David] Plouffe, Axelrod -- the statements that are being made, and this is being thought out. It's not spontaneous and it's just not true."

Kelly also wanted to know if Wilson had faced a backlash after calling Obama a liar and if the president's campaign could expect the same.

"I received over a half a million letters from people across the United States -- supportive -- and then, in the last election, my percentage of victory went from 7 percent to 10 percent and that's why I don't even have an opponent today, because the American people and the people of the 2nd District of South Carolina know I'm a gentlemen," the tea party-backed congressman explained.

"I think its very important to apologize for a town-hall moment, but these people are being very contrived. And I think it's going to backfire on them because the American people know better, they know the truth now."