Simon Cowell is interviewed following the Variety Children's Charity 2010 Hollywood World Conference in Los Angeles May 23, 2010. REUTERS/Phil McCarten (UNITED STATES - Tags: ENTERTAINMENT)

Simon Cowell claims he "propelled" Cheryl Cole into a "different league".

The 52-year-old music mogul would love to work with the 'Call My Name' singer - who he sensationally fired from the US version of 'The X Factor' last year - again and thinks her success away from Girls Aloud is all down to him appointing her as a judge on the UK talent show in 2008.

He said: "Even though we went through that pretty horrible period, I could look Cheryl in the eye and say what I did for her in those two years propelled her into a different league. I always said to her the door is permanently open. It's entirely up to her what she wants to do."

Simon admits the sacking of Cheryl - who was asked to return to the UK programme when replaced by Nicole Scherzinger on the US judging panel - "ended badly" and he wishes it hadn't happened.

He told GQ magazine: "If I could reverse time it wouldn't have happened. It was an in-the-moment decision where you put your producer's hat on. I just thought she was more comfortable on the UK show. She was hurt. It all ended pretty badly, to be honest."

Simon also appeared to hit out at Cheryl's manager, blaming "negative" influences for the 28-year-old beauty turning down the offer to return to the UK show.

He said: "I had negotiated a very, very good deal for her to come back to The X Factor in the UK.

"But when you've got someone negative in your ear, you know, who is putting a negative slant as opposed to a positive slant, then you might get swayed.

"I think if it was left down to her she would have done it." - Bang Showbiz