David Beckham has been approached to play a bad guy in a new movie.

The retired soccer star - who announced he was quitting the sport earlier this year - has been asked by Colin Firth to star in The Secret Service and director Matthew Vaughn is so confident he will agree to appear, he has already had a villainous part written for him.

"Becks was asked by Colin Firth if he'd like to be in the movie but he is yet to fully commit. He loves movies and fancies appearing on the big screen -- but just as a one-off, not a full-time career," a source said.

The film - which is based on a spy graphic novel by Mark Millar and Dave Gibbons - stars Colin and Michael Caine as superagents fighting a team of villains headed by Samuel L. Jackson and will also feature cameo appearances from stars including Elton John.

David - who has children Brooklyn, 14, Romeo, 10, Cruz, eight, and Harper, two, with wife Victoria - has previously been tipped for movie success by his spouse. "I think he would be really good at acting. He'd be a great James Bond," she has said.