Updated

Ben Affleck didn’t feel like a true thespian until he locked lips with another guy, according to Kevin Smith.

Smith, Affleck’s director in 1997’s “Chasing Amy,” screened the movie for its 20th anniversary on Saturday at the Outfest film festival in Los Angeles, where he dished on Affleck kissing Jason Lee onscreen.

“A man kissing another man is the greatest acting challenge an actor can ever face,” Smith, 46, recalled telling Affleck, according to Gay Star News.

After shooting a scene in which he and Lee lock lips, Affleck reportedly told Smith, “Now I’m a serious actor.”

After the movie came out in 1997, Affleck noted how difficult the scene was for him.

“I’m not homophobic,” he told “Entertainment Tonight” at the movie’s premiere in 1997. “I just … I guess I am more than I thought, in that, it was just difficult for me you know? And I didn’t think it would be. I really backed down from it in a way. I really could have done more of a committed job.”

In 2012, he expressed regret at the way he handled the kiss.

“I was supposed to kiss Jason Lee,” he told The New York Times in 2012. “[My peers said] you were a really great actor if you could convincingly play homosexual as a man, and I just blew it. The kiss is in there, but it looks like ‘Tom & Jerry.’ It’s not anything good … I tried to go open-mouthed, but something in me was, ‘Take your tongue back.’ And I was like, ‘No, you can do it! Push!’ It was not my proudest moment.”

This article originally appeared in the New York Post's Page Six.