Gary Oldman says Clint Eastwood gave him his best filmmaking advice.

The 'RoboCop' star made his directorial debut in 1997 with gritty drama 'Nil by Mouth' and credits the screen legend - who is also a successful director - for helping him make the move behind the camera.

He said: ''Clint Eastwood gave me the best advice when I directed, 'Get more sleep than your actors.' ''

The 55-year-old star also says he was shocked when he met another huge screen star, Sir Michael Caine, because he didn't expect his reaction.

He told Us Weekly magazine: ''When I first met Michael he asked for an autograph for his daughter.''

In 1986, Gary won widespread critical acclaim for his portrayal of late Sex Pistols star Sid Vicious in biopic 'Sid and Nancy' but he insists he doesn't even remember the role which brought him to fame.

He said: ''I don't' remember doing 'Sid and Nancy'. I've wiped that from the hard drive.''