Actor Gerard Butler loves showing off his bum on the big screen – because he’s proud of his finest asset.

But the Scot fears moviegoers think an a**-baring scene is written into his contract – just so he can get naked.

Grauman's Chinese Theatre, Gerard Butler

He tells WENN, “I love to show my rear end in roles. I fear it’s becoming a bit of a habit, a tradition that I have to show my a** in every movie that I can.”

Butler bares all in new film Law Abiding Citizen and admits that scene was very much in keeping with his character in the film.

He adds, “This was always a great scene in the movie and actually speaks volumes about this character and part of the wackiness and unexpectedness that happens… He’s completely unpredictable and so when he strips off it makes sense.

“I mean there’s a genius behind that and if it means I have to bare my ass again than so be it.

“I’ve always had a skinny, tight a** but I had to bulk up for this film; I was inspired by watching (Robert) DeNiro in Taxi Driver during the scene where he’s doing the push-ups and he’s so cut. A lot more is said in that than somebody just being big and kind of a meathead.”

But Butler admits he doesn’t always enjoy the work that comes as he prepares to bulk up for a movie role: “Whenever I make those decisions to be naked, I go, ‘Oh s**t here’s another three months of being on a diet and getting that body back!'”