Christina Aguilera's comeback single has leaked online.

New song, 'Your Body', surfaced on the internet last night (23.08.12), but is believed to be a demo and slower than the final version of the song.

The track is an mid-tempo R&B dance song which sees Christina sing ''All I wanna do is f**k your body'' in the chorus.

The star has also previewed new purple hair on twitter and posted a number of photos from the set of the video for 'Your Body'.

She said ealrier this week: ''Its finally here- MUSIC VIDEO shoot day!!!!!!!!! Get ready guys!!!!!!!!!! (sic)''

The new track is a preview of Christina's seventh album, which will be released this autumn.

The as-yet-untitled record will follow up to 2010's 'Bionic', which was a commercial flop, although Christina's profile was recently boosted when she appeared on Maroon 5's huge 'Moves Like Jagger' single.

She is also a mentor on the US version of 'The Voice' and contributed a number of songs to the soundtrack to film 'Burlesque' - which she also starred in - which was a hit, selling over a million copies worldwide.