Nicole Scherzinger quits as X Factor judge

Nicole Scherzinger has quit The X Factor.

The former Pussycat Doll, who has been a judge on the ITV talent show for the past two series, has reportedly made the "agonising" decision to leave to focus on her music career.

A friend of the star told The Sun: "It breaks her heart, but Nicole is sad not to be able to go back to the show this year. She has agonised over this decision for months.

"She put her music career on hold last year but now she has to focus on her music."

The news comes just days after X Factor boss Simon Cowell announced he would return for the next series, replacing Gary Barlow, and would like Cheryl Cole to join the panel once again.

Show bosses were keen to keep Nicole, 35, who recently signed a new recording contract with Sony, but those close to Simon say she will "always be part of the 'X Factor' family."

Nicole is believed to have inked a £3 million recording deal and is due to release a new album in coming months, her first new material in three years.

Simon admitted this week he's been in talks with Girls Aloud singer Cheryl, 30, to come on board after a three-year absence but said it's been difficult to try and persuade her.

Speaking about her possible return, he said: "To be fair to Cheryl, it hasn't been about the money with her. It's about whether she wants to do it and whether she can handle the pressure, so I'm not quite sure yet [if she will come back]."

Simon added: "She had her poker face on."

The 54-year-old music mogul wants to recreate the success of the series in 2010, when One Direction started their journey to becoming the world's biggest boy band.

The show pulled in 19 million viewers and saw Matt Cardle crowned the winner, while just 11.5 million watched as Sam Bailey was named champion last year.

Meanwhile, sources say Simon is also keen to sign Rita Ora as a new judge on the show.