Ozzy Osbourne has launched a social media campaign which will eventually reveal the cover art for a mystery new project.

The Prince of Darkness is asking fans to share the hashtag #OzzyRules on Twitter and Facebook, with the aim of unveiling artwork – which could be for a new solo album or a completely different project.

A message on his Facebook page says: “Calling all fans – help unscramble Ozzy’s new cover art by using the hashtag #OzzyRules on Facebook and Twitter. The more you share the sooner it unlocks.”

Visit Ozzy's Tweematic page to find out more.

The Black Sabbath frontman's last solo album was 2010's Scream. His touring guitarist Gus G said in a recent interview that Ozzy "definitely" aimed to make a follow-up, while the frontman himself reported in 2011 that he wanted to get "back to basics."

Sabbath's most recent album was last year's 13. Despite its success the band remain uncertain about their future.