Paul Bettany's daughter calls Johnny Depp ''Uncle Fun''.

The 43-year-old actor has revealed his and wife Jennifer Connelly's three-year-old daughter Agnes is fascinated by the 'Pirates of the Caribbean' star because he owns an island, so much so she came up with an inventive nickname for him when they were holidaying together.

Speaking at a London press conference to promote comedy/action film 'Mortdecai' - in which the pair both starred - Paul said: ''She calls him Uncle Fun.''

Johnny - who splashed out $3.6 million on his own Caribbean island in 2004 - joked: ''Many people do.''

Paul added: ''If you're wondering why my children call him Uncle Fun it's because he has a f***ing island.''

Johnny jokingly replied: ''Which is indeed fun!''

Paul - who also has step-son Kai, 17, and 11-year-old son Stellan, who is named after his 'Kiss Kiss (Bang Bang)' co-star Stellan Skarsgard - also revealed Agnes inspired him to create a comic moment in the movie, which sees Johnny play debonair art dealer Charlie Mortdecai.

He added: ''I'm carrying Johnny up the escalators because he's drunk in the film and he says 'Uppy uppy'.

''That's because my daughter Agnes, we were on holiday together and she kept walking up to Johnny and going, 'Uppy uppy.' ''