U.S. actor Jim Carrey, left, poses with his partner Jenny McCarthy as they arrive for the world premiere of the film 'A Christmas Carol' in London, Tuesday, Nov. 3, 2009. (THE ASSOCIATED PRESS/Matt Dunham)

LONDON - Jim Carrey, Colin Firth and Bob Hoskins appeared in central London to switch on the city's Christmas lights and attend the world premiere of a 3-D film, "A Christmas Carol."

The actors came to the British capital to promote Robert Zemeckis' animated movie, which features their voices.

The three stars switched on the lights at Oxford Circus and Regent Street - London's main shopping areas - and at St. Paul's cathedral on Tuesday.

The premiere is to be screened at a cinema on central London's Leicester Square on Tuesday evening.