Will Smith has jumped to the defence of former troubled star Britney Spears in a candid interview.

The actor told a US publication that he fully expects his children to go off the rails as it's only natural to want to rebel at such a young age.

Will told Essence magazine, "That's what you do when you're young.

"Compared to some of the stuff that I did, and got away with, Britney is keeping it real tame.

"I just wasn't in the media like that at that age."