Bridget Jones star goes undercover

Greg Kinnear, Renée Zellweger and Chris Rock promoting Nurse Betty

US actress Renée Zellweger has told how she prepared for her forthcoming role as British literary heroine Bridget Jones - by working for the book's publisher.

Speaking at the Cannes Film Festival, the 31-year-old actress said she adopted the name Bridget Cavendish and followed the example of the fictional character by finding a job at the London offices of Picador.

"I've been working with it for almost two-and-a-half months and living in London for two months," she told reporters after a screening of her new film, Nurse Betty.

Zellweger said she had spent "a few weeks" working in London

"I've been working as Bridget Cavendish. I've rather enjoyed that, actually, it's the first time I've used my college degree."

Zellweger - the partner of comic actor Jim Carrey - assured fans of Helen Fielding's novels that "Bridget will be absolutely British".

"I love the character and I love the book and I'm very excited about it," she said.

"I'm trying to familiarise myself with the culture. I feel a very strong responsibility to make sure she's as truly British as I can make her.

"She's experiencing situations that are universally challenging. Any woman in America and around the world who has pursued a career can relate to that."

But she said it would be "a bit premature" to demonstrate her British accent.

Zellweger was joined at the press conference by her Nurse Betty co-star Greg Kinnear and director Neil LaBute.

Another Cannes star: Calista Flockhart

She plays a woman who retreats into the fantasy world of her favourite soap opera in the film, one of 23 competing for the Palme d'Or.

Meanwhile, Holly Hunter and Calista Flockhart were also in Cannes to promote their new film, Things You Can Tell Just By Looking At Her.

Co-starring Glenn Close and Cameron Diaz, it was made by first-time director Rodrigo Garcia - the son of Nobel prize-winning writer Gabriel Garcia Marquez.

He admitted to being surprised at the big names he had attracted to the movie, which is out of competition at Cannes.

"Only a madman would think he could get a cast like that for a first film," he said.