Fox News star Tucker Carlson is under attack from the Clinton-backed Media Matters for America — but he's not backing down.

And on Monday, Carlson unloaded with his own attacks.

Media Matters, a liberal watchdog group run by former Secretary of State Hillary Clinton's self-described "attack dog", claimed over the weekend that they discovered old radio interviews of Carlson on shock jock "Bubba the Love Sponge" shows where he laughs at sexist jokes and says inappropriate things.

"Between 2006 and 2011, Tucker Carlson spent approximately an hour a week calling in to Bubba the Love Sponge, a popular shock jock radio program where he spoke with the hosts about a variety of cultural and political topics in sometimes-vulgar term," Media Matters said in a statement Sunday.

The group has demanded Carlson resign — or that Fox News fire the popular late night opinion host.

Carlson released his own statement in response… and it was not what liberals expected to hear.

"Media Matters caught me saying something naughty on a radio show more than a decade ago," Carlson said Sunday night… before dropping a bombshell.

Rather than express the usual ritual contrition, how about this: I'm on television every weeknight live for an hour," Carlson's statement continued.

"If you want to know what I think, you can watch. Anyone who disagrees with my views is welcome to come on and explain why."

On social media, Media Matters are their political allies have started a campaign to pressure Carlson's advertisers to drop their support for the Fox News host.

The hashtag #FireTuckerCarlson trended on social media all of Monday, with activists on both sides exchanging their thoughts.

And on the other side —

So far, advertisers on Carlson's show have resisted the political hit piece.

"Advertising media spend is determined based on demographics and psychographics, not politics," Mitsubishi told The Huffington Post when asked if they were going to withdraw their support.

"Our strategic marketing intent is to share our key product news with consumers through a variety of media channels," their spokesman said. "We will monitor the situation and adjust our advertising if necessary."