Singer Cheryl Cole

Cheryl Cole is planning to release an autobiography.

The 'Call My Name' singer has reportedly signed a "big money" deal with publishers Harper Collins for the tome - which will hit stores in the autumn - and has vowed to tell all about her marriage to soccer player Ashley Cole, who she split from in 2010 amid revelations of his infidelity.

A source told The Sun newspaper: "She signed the deal for big money so she won't be able to hold back on details. Ashley should be worried."

Cheryl, 28, is said to have already chosen a ghost writer to pen the book and has spent months reading through her old diaries now she is ready to "speak out" about her marriage,

relationship with her Girls Aloud bandmates and her sensational sacking from the panel of the US version of 'The X Factor' last year.

A source told the Sunday Mirror newspaper: "Cheryl's been thinking about doing this for a long time and has spent months ­preparing, going through old diaries. She wants no stone left ­unturned.

"After remaining silent for so long it feels like the right time to speak out.

"She will share all the ins and outs of her marriage breakdown as well as her life as a member of Girls Aloud.

"She won't be going out to attack people but equally she wants to set the record straight." - Bang Showbiz