Cher has confirmed that she will release duet 'The Greatest Thing' with Lady Gaga.

The track,written by Lady Gaga and producer RedOne, will appear on Cher's forthcoming new album.

Cher revealed last month that Gaga would duet on the track, telling fans over Twitter: ''Can't wait till GaGa puts her Voice on "The Greatest Thing" SHE WILL ROCK IT SO FKNG HARD! (sic)"

The collaboration has now been confirmed as the lead single from Cher's new album. She told fans over Twitter that the 'The Greatest Thing' will be released in SEPTEMBER."

An early demo version of 'The Greatest Thing' appeared online last year.

Meanwhile, Lady Gaga has unveiled the video for her new single ‘You And I’ - and you can watch it now on Gigwise.

Cher and Lady Gaga - 'The Greatest Thing' Demo:

Lady Gaga - live photos