Begin Again actress Keira Knightley admits she was recently mistaken for Interstellar star, Anne Hathaway.

29-year-old Knightley revealed she was approached by a fan at Toronto Airport in Canada who believed she was the 32-year-old star and accused her of being rude because she refused a photo.

Speaking to Australia's Daily Telegraph newspaper, Keira said, ''At the airport a woman mistook me for Anne Hathaway.

''Actually I think I have to apologise to Anne Hathaway because the woman (at the airport) thought I was being really rude as Anne Hathaway not giving her a picture as Anne Hathaway but I was really only saying that I promised I wasn't Anne Hathaway -- which I am not.

''Actually it's the first Anne Hathaway I have had. Generally I get a lot of Rachel Weisz and Natalie Portman.''

Knightley recently announced she is expecting her first child with her husband James Righton.