Diane Keaton accused Stephen Colbert of being a “‘sexual pervert” while constantly bringing up her interviewer’s bum instead of her new memoir.

Late Night reported that Keaton appeared on ‘The Colbert Report‘ on Monday night. Her stated purpose was to promote the paperback release of her memoir, ‘Then Again.’

But the interview quickly descended into chaos. The Oscar-winning actress started things on a confrontational note by asking Stephen Colbert if he was still running for President- and then adding that she wouldn’t vote for him.

Instead of her book ‘Then Again,’ Diane Keaton discussed Colbert’s posterior. She claimed that Stephen Colbert didn’t get invited to the White House Correspondents’ Association dinner because he didn’t deliver his 2006 speech naked. Then she declared that she didn’t want to see his naked behind.

Baffled by the constant mention of his posterior, Colbert wondered aloud if she had misinterpreted his backstage hug before ‘The Colbert Report’ started. Diane Keaton replied, ”I’m bringing you up on charges. … I really mean it.”

Stephen Colbert attempted several times to steer the interview back to Keaton’s book ‘Then Again’ by bringing up Keaton’s relationship with her late mother Dorothy Deanne. ”Did your mother want you to be an actress?”

But Diane Keaton completely ignored his line of inquiry. ”Now you know why I wouldn’t vote for you,” she stated. “Because you’re a sexual pervert.”

The rather confused Stephen Colbert finally demanded that “before I encourage my viewers to buy the book,” Diane Keaton needed to say “one [bleeping] thing about it.” Keaton’s only response was to laugh nonstop.

As ‘The Colbert Report’ segment drew to a close, Diane Keaton suddenly asked if she would make a good sidekick on a talk show. She then got up to leave the stage just as suddenly, without waiting for a reply from Stephen Colbert.