British funnyman Russell Brand has spoken out in defence of troubled pop star Justin Bieber as a racism scandal threatens to engulf the singer.

The Baby hitmaker has been under fire since the leak of a video which showed him making a racist joke and using the 'N-word'.

Bieber issued a public apology, branding his behaviour "reckless" and "immature", but the scandal has failed to dampen down.

Brand has now spoken out in defence of the embattled singer, who was a teenager when the video was shot.

In a video posted on YouTube.com, Brand says, "It was ages ago when he used to have That hair cut. You can't do him for stuff he (has) done when he had that hair cut... Unless we're going to explicitly say the role of celebrities is we're going to make them really, really famous and then we're going to destroy them and rip them up in a public square with fish hooks... which... I'm not against but we might as well own up to it if that is what we're up to, otherwise just let him off. Of course it's wrong to say the 'N-word', but he's a child."