Keira Knightley has said Anna Karenina marks an important development for her as an actress, Belfast Telegraph reported.

Director Joe Wright has praised the 27-year-old actress for the new maturity she shows in her performance as Tolstoy's tragic heroine.

Keira told Deadline.com: "You don't wake up the morning and say, 'I am a woman now. Wow, I'm feeling really mature.' But, yeah, if the question is, 'Would you have played this role like this five years ago?', the answer is no."

The Pirates Of The Caribbean star also revealed she felt more pressure playing heroine Elizabeth Bennet in Pride And Prejudice as she is so well liked, where as the multi-faceted role of Anna Karenina was less daunting.

She said: "There are really so few wonderful roles for women, she's up there as being incredibly complex and incredibly interesting.

"I was much more frightened playing Elizabeth Bennet; she's a character that you immediately fall in love with. Anna is absolutely not a character like that, so I don't think I felt the same terror as I felt taking on Elizabeth."