Justin Timberlake's dig at Britney

Justin Timberlake calls Britney a 'wannabe'

Justin Timberlake made a thinly-veiled dig at his ex-girlfriend Britney Spears as he inducted Madonna into the Rock and Roll Hall of Fame.

While giving a speech about Madge, he recalled how, while they were collaborating on her new album Hard Candy, she ordered him to drop his pants to give him a vitamin B12 shot.

'She gave me a shot in my a-- and looks at me and says, "Nice top shelf,"' he told the audience. 'That was one of the greatest days of my life.'

But he also took the opportunity to take a jab at Britney in the process.

'She has still found time to kiss someone I may or may not have publicly kissed myself while I was in the audience,' Timberlake said of Madonna. 'Of course, you know I was talking about Sean Penn.'

He continued: 'The world has always been full of Madonna wannabes, and I might have even dated a couple.'

Put your claws back in, Justin!

CLICK HERE to see pics of Madonna and Justin at the 23rd Annual Rock and Roll Hall of Fame Induction Ceremony.