Nicolas Cage turned down the role of 'Shrek' because he was too vain.

The 49-year-old actor is friends with studio chief Jeffrey Katzenberg and was initially asked to voice the friendly green ogre - the role which eventually went to Mike Myers - and he admits he sometimes regrets turning the animated movie down.

He said: ''We were talking about 'Shrek' and I just didn't want to look like an ogre.

''Maybe I should have done it looking back.''

Nicolas has finally teamed up with Jeffrey for another animated film, 'The Croods', and though the 'Con Air' star was apprehensive about his animated alter ego, caveman Grug's appearance, he was delighted to be a part of the movie.

He said: ''They all came out to New Orleans and met with me and showed me a picture of Grug and said, 'Look Nic, this is how I see you'! I said, 'I hope I don't really look like that, but I think I'll do this'.

''What really got me about Grug is his emotional transformation from an overprotective father who is surviving but not living and then he learns how to let go and live and I like that. That's what appealed to me most. I like a movie that can make you laugh and make you cry.''

'Shrek' was released in 2001 and grossed over £300 million at the worldwide box office, and went on to spawn a number of sequels and spin-offs.