Sir Elton John is secretly shy.

Singer Rufus Wainwright - who sought guidance from the 'Rocket Man' hitmaker in 2000 when he was struggling with an addiction to crystal meth - claimed the flamboyant star is very quiet away from his public persona and has little belief in his own abilities.

He said: "I don't think people are aware of how shy he is. He's a bit like The Wizard of Oz. On the one hand there's this big pomp and circumstance, but really beneath it all there's this very sweet little guy who's constantly feeling very insignificant, which is ironic of course. What I'm saying is, he's quite shy."

While the 36-year-old star claims it was Elton who persuaded him to seek therapy for drug addiction, his problems got so bad, he even temporarily went blind.

Rufus added to Q magazine: "I lost my sight for one or two hours. I can't quite gauge it exactly. During that period of losing my sight, I was also losing my mind. I could feel my sanity lifting off, and I wasn't sure it would come back again. But it did and thankfully I'm still here today."