Sylvester Stallone is set to retire from acting.

The 63-year-old actor - best known for his roles as boxer Rocky Balboa in the 'Rocky' movie series and troubled soldier John Rambo from the 'Rambo' franchise - says his new movie 'The Expendables' could be his last as the time is right for him to move on.

He said: "I'm on borrowed time. At this age I hear the ticking clock and it's as loud as the gong on Big Ben."

However, he doesn't want to leave the acting world completely and would like to showcase his talents behind the camera.

Speaking at the Los Angeles Film Festival, where he received a special award for his successful career, Stallone said: "The ultimate ambition is to follow in Clint Eastwood's footsteps and move on to directing films without me having to be in them.

"I'm on borrowed time and know my longevity will be predicated on being able to make that move."

In 'The Expendables', Stallone plays a gang leader of veteran mercenaries on a deadly mission and features cameo appearances from Arnold Schwarzenegger, Bruce Willis and Mickey Rourke.

It is due for release internationally throughout August.