Nicholson admits he is "not much of a raver anymore"
The 66-year-old superstar actor has been infamous for his partying and womanising but now says his raving days are over.
"I've been walking pretty slow upstairs for a long time," said Nicholson.
"All my pals seem to be out of town. I'm just here for a couple of days so I won't be able to play Jack the Lad on this trip.
"All good things come to an end. I'm not much of a raver any more. I think it's unattractive."
Nicholson admits that he can see something of himself in the role he plays in is latest flick Something's Gotta Give, in which he stars opposite Diane Keaton as an older man with a penchant for younger women.
The actor was in London to promote the romantic comedy, which also features Keanu Reeves and Amanda Peet.
The film, which opens in the UK on Friday, sees Nicholson play an ageing lothario who falls for Keaton, the mother of his latest girlfriend.
Nicholson, who has dated a string of younger women, including a long affair with Men In Black II star Lara Flynn Boyle, said the film's director Nancy Meyers had written the script with him in mind.
He said: "Nancy wrote the script for me. I talked to her about it in advance while she was working on it.
"I guess it's got some good pieces of what my life has been like."
Keaton, 58, scooped a Golden Globe for Best Comedy Actress and has been nominated for a Best Actress Oscar for her part in the film, which has proved a hit in the US.
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