Robin Williams was turned down for a role in 'Harry Potter' because he wasn't British.

Robin Williams

Robin Williams

The late Hollywood actor - who committed suicide in August 2014 aged 63 - was reportedly desperate to portray the role of Hagrid, the half-giant and half-human gamekeeper and Keeper of Keys and Grounds of Hogwarts, played by Robbie Coltrane.

The 'Mrs. Doubtfire' star is believed to have begged the director of the blockbuster franchise, Chris Columbus, to take him on for the part, but he rejected his pleas.

The film's casting director, Janet Hirshenson told The Huffington Post: "Robin had called [Columbus] because he really wanted to be int he movie, but it was a British-only edict.

"And once he said no to Robin, he wasn't going to say yes to anybody else, that's for sure, It couldn't be."

Williams isn't the only person to be rejected by the director of the franchise - based on the best-selling novels by author J.K. Rowling - as Eddie Redmayne was also turned down for the part of Tom Riddle, despite later appearing in the spin-off 'Fantastic Beasts and Where to Find Them' in the leading role of Newt Scamander.

The 34-year-old actor previously revealed: "I actually auditioned to play Tom Riddle while I was at university.

"I properly failed and didn't get a callback."

Riddle only appears in 2002's 'Harry Potter And The Chamber of Secrets' and was played by Christian Coulson.

However, Redmayne never lost hope that he would one day be cast in a part in the films.

He added: "Over the years, I always hoped I might be cast as a member of the Weasley family - I'm colour blind, but I've always been told where there's a tinge of red to my hair - but unfortunately not."