Ted star Mark Wahlberg has warned Baby singer Justin Bieber to clean up his act, or risk ruining his career.

The 42-year-old actor hopes that the 19-year-old pop sensation will follow his example and turn his life around.

Speaking during a live web chat with The Sun, Wahlberg said: "Justin, are you listening? Don't be so naughty... Be a nice boy, pull your trousers up, make your mum proud... He's a teenager living in a different day and age."

Wahlberg continued: "He's a nice enough kid and you're going to be a teenager. But if you're being a teen in the spotlight you're going to be criticised for it. This career can be shortlived - you might as well be the best you can while you're doing it."

The actor finished by saying a movie collaboration with Bieber "could still happen".