The Saturdays are to be given a rock makeover.

The British girl band - Una Healy, Mollie King, Frankie Sandford, Vanessa White and Rochelle Wiseman - have teamed up with former Busted star James Bourne for 'Forever Is Over', which will be the first single from their second album.

The Saturdays are keen to distance themselves from their pop reputation, and their UK chart rivals Girls Aloud, and see the song James has written as the perfect way to do this.

A source told Britain's Daily Star newspaper: "'Forever Is Over' will be the song which finally distances The Saturdays from all the Girls Aloud clones remarks. It's totally unlike anything they've ever done before. It's a big 'f**k you' to a boyfriend after a break-up, and sounds nothing like Girls Aloud would ever release either.

"Everyone around the band is very excited as they've really started to hone their own sound. James wrote all of Busted's number ones and a massive bunch of McFly hits too, so he knows what he's doing when it comes to pop and rock with a mainstream edge."

James is now a successful singer-and-songwriter and lives in Los Angeles.

The Saturdays' new album, as yet entitled, will be released in October and is expecting to have an edgier feel than their debut, 'Chasing Lights'.

The source added: "This is The Saturdays as you would never expect them. They are keen to push themselves with a stronger sound."