'New Britney single' leaked online

Rex Features

A track reportedly from Britney Spears's forthcoming album has been leaked online.

The popstar's comeback LP Circus is due for release on December 2, her 27th birthday.

The song, entitled 'Candy From Strangers', appears online at www.britneyspearscircusleak.com and features rap newcomers Laze & Royal.

ITN reports that the sudden leak has cast doubt on the single's authenticity.

Spears's previous album Blackout was released last November.