Sir Ian McKellan says homophobia is as big a problem as racism in Hollywood.

He told The Guardian newspaper: "No openly gay man has ever won the Oscar; I wonder if that is prejudice or chance."

Commenting that straight actors Tom Hanks, Philip Seymour Hoffman and Sean Penn have all won Best Actor gongs for playing gay men, he said: "How clever, how clever. What about giving me one for playing a straight man?"

Ian has been nominated twice, once in 1998 for Best Actor for 'Gods and Monsters' and again in 2001 for Best Supporting Actor for 'The Lord of the Rings: The Fellowship of the Ring' and admitted his disappointment that he was not able to break the cycle.

He said: "My speech has been in two jackets … 'I'm proud to be the first openly gay man to win the Oscar.' I've had to put it back in my pocket twice."

Ian spoke out as controversy continues to rage over the lack of diversity at the Oscars.

With stars including Jada Pinkett Smith and her husband Will Smith boycotting the ceremony in protest at the lack of black nominees, Ian said that the Academy needs to change how it operates.

He explained: "If you are trying to have a career, as a black or Hispanic actor in a state – California – where white people are now the minority, and you are being judged by an Academy where the vast majority are white, male, middle-aged and old … well, perhaps that is the wrong yardstick."