Cheryl Cole has opened up on what life was like in Girls Aloud before they went on a prolonged break.

The popular girl group formed in 2002 on Popstars: The Rivals but went their separate ways in 2009 to pursue solo careers.

Speaking in her new autobiography Cheryl: My Story, Cole said that bandmate Nadine Coyle's desire to break solo in the US caused some problems within the band.

She admitted that Coyle brought her own manager on tour with Girls Aloud, which proved to be a breaking point. Cole said:

"Having her manager actually on tour with us was crossing the line, and that's when I knew that it was finally time for us to take a break."

The 'Call My Name' star, who insists there was no bad blood between herself and Coyle, said of the Irishwoman's solo plans:

"It was no secret Nadine was trying to launch a solo career in America. She'd been living in the States for several years by now and was forever travelling back and forth. I felt we were lucky she was prepared to split herself in two."

Girls Aloud look set to reunite next week (October 19) to celebrate their 10th anniversary, with the band launching a mysterious countdown clock online.