Bill Burr has defended his wife Nia Renee Hill after she flipped off Donald Trump at an Ultimate Fighting Championship match earlier this month.

The comedian, 55, called his spouse's actions "hilarious" while appearing on a recent episode of The Rich Eisen Show.

"I love my wife," Bill told the host. "You know where you stand with her."

In footage which has since gone viral on social media, Nia can be seen raising two middle fingers behind the former U.S. president as he approached his ringside seat to cheers from the crowd.

While her actions sparked some negative comments from social media users, Bill defended his wife's right to free speech.

"The guy walked into the arena, everybody cheered, she gave him the finger, nobody got arrested," he told Rich Eisen. "That's why this country's great! Everybody expressed themselves."

The Old Dads actor added he was surprised the moment went viral.

"I don't know about you but I came there to go to the fights," Bill said. "I didn't know I was going to the Republican National Convention."

Bill and Nia have been married since 2013. They share two children - a daughter Lola, six, and a three-year-old son whose name has not been publicly disclosed.

Old Dads is currently streaming on Netflix.