Hollywood stars Renee Zellweger and Richard Gere turned out for the world première of their film version of globally successful musical Chicago.

Zellweger went on a 10-minute walkabout in London's Leicester Square to meet fans who had queued for hours in the cold to catch a glimpse of the star.

Richard Gere arrived with his wife

The actress, who has been filming in east Europe, said: "I'm not freezing at all, this is a beautiful spring day compared with the Transylvanian mountain tops."

The film's other lead, Catherine Zeta Jones, did not attend as she is six months pregnant with her second baby.

Chicago was first written as a play in 1926 and the musical version made its debut in 1975, going on to become a global hit.

'Thrill'

Speaking about her audition for Chicago, Zellweger said: "I was so nervous because it is the first time I've opened my mouth to sing in front of anyone but my dog.

"But being in the movie was a thrill for me. Compared to Broadway dancers I wouldn't get past the first cut in the real world, but I just got this lucky chance."

Gere who attended with his new wife, former Bond girl Carey Lowell, said: "It took me five months to learn how to do it and it was very hard work. I was so shy about it I wouldn't even rehearse in front of my wife."

Gere said the film's big stars were all extremely impressed by each other's performances: "We didn't know each other well before we started and we were all thinking 'I wonder if she can do it, I wonder if he can do it'."