Ashton Kutcher has revealed acting is his licence to fool around without getting trouble with his wife.

The Punk'd star, whose character in new romantic comedy What Happens In Vegas marries Cameron Diaz after a night of drunken debauchery, is married to Demi Moore, but considers a movie to be a "get out of jail free card".

Ashton said, "what's great about a movie is you get to go and do whatever you want to do and you have an excuse as to why you did it. So it's like a giant get out of jail free card and you get paid to do whatever you want and then you have an excuse as to why you did it.

"I mean I get to kiss other girls, I get to act like an idiot, I get to say stupid things and I'm not really accountable as that was my character."

The film is directed by British director Tom Vaughn, the man behind hit TV drama Cold Feet.

Asked if he'd ever done something while drunk and regretted it the next morning Tom said, "Definitely. Last summer while we were filming the movie in New York. I woke up one morning and we'd all gone out the night before to a karaoke bar and I had flashes in my head of me singing Blur's 'Parklife' to a room full of movie stars.

"I just thought, 'What have I done?!'"