Keira Knightley delighted fans at the UK premiere of her new film Atonement by going on a walkabout to sign autographs for her admirers.

The 22-year-old star was in London's Leicester Square before the showing of the movie at the Odeon Cinema.

Knightley, who is being tipped for an Oscar nomination for her role as Cecilia Tallis, wore a silver-grey Rodarte dress, slashed across the front, and a tiara in her hair.

Directed by Joe Wright and adapted from the wartime novel by Ian McEwan, it is being hailed as one of the strongest British films in years.

It is in official competition for the Golden Lion award for best film at the Venice Film Festival and has been warmly received by critics.

The story tells of Cecilia Tallis, an upper class beauty whose fledgling love affair with the housekeeper's son, played by James McAvoy, is
destroyed by a tragic misunderstanding.

McAvoy also went over to greet his fans and sign autographs. Knightley said: "I think we are all proud of the whole film, mostly we are proud of Joe Wright, the director."

She said: "I find him an incredibly exciting director, and he's given me two of the best characters I've played."

Asked if she had a preference for any particular kind of role she said: "No, I think the whole point is to change. I'm really lucky and I get the opportunity to change, and you can't ask for much more than that as an actress."

Asked about her chances of winning an Oscar, she said: "The fact that the film is in the same sentence as the word Oscars means we've done a good job already. If it doesn't get a nomination, it doesn't take away from how
proud I am.

"I knew it was quite good when my mum went to see it and was crying." McEwan, asked about the film's chances of an Oscar, said: "It would be the film that wins an Oscar, not the book, it will be great if it does."

Asked what he thought of the movie, he said: "I think James McAvoy and Keira have turned in really quite exceptional, thrilling performances.
"I think playing the character in the rather brittle way she does, means that when they have their great sex scene in the library, it's like a dam-bursting."