Gregg DeGuire / WireImage / WireImage 1 / 11
Gregg DeGuire / WireImage / WireImage 1 / 11

Ozzy Osbourne is urging fans to celebrate his 65th birthday on Tuesday by donating money to Britain's Royal Marsden Cancer Charity.

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The rocker officially becomes a pensioner in his native England on Tuesday and he has taken to Twitter to urge fans to give generously.

He tweets, "I'm using my bday (tomorrow) to raise money for @royalmarsden! Give a gift and donate to help cancer patients."

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Ozzy isn't the only star to use his birthday to raise donations for the charity this year. Former Spice Girls star Mel C, The Wanted stars Nathan Sykes and Max George and Sir Paul McCartney have also urged fans to give cash to The Royal Marsden.