Shayne Ward is "gutted" he can't take part in 'The X Factor: All Stars'.
The former 'Coronation Street' star - who shot to fame when he won the second series of the singing competition in 2005 - was asked to return to the show for the upcoming special featuring past contestants but already had other commitments so had to decline.
He told Closer magazine: "I can't do 'All Stars' because I'm contracted for something else.
"It's gutting because I loved that show - I'm so proud of it."
However, the 'That's My Goal' hitmaker will be tuning in to watch.
He added: "I'll be there as a fan and I can't wait to see [the others] who take part. It's going to be fun to watch."
Shayne was mentored to victory on 'The X Factor' by Louis Walsh but they have lost contact over the years and he'd like to see him and show boss Simon Cowell again.
He said: "I've not spoken to or seen Louis in many years.
"It's the same for Simon, although I did see him earlier this year at the Pride of Britain Awards.
"I love Simon - they were both my bosses for many years so it would be nice to see them again."
Meanwhile, the 34-year-old star - who has daughter Willow, two, with fiancée Sophie Austin - has been working hard with his partner to stay in shape.
He said "Sophie and I train together. I champion her like she champions me.
"She looks absolutely incredible - I think she's down two dress sizes.
"I never thought I'd be able to say I enjoy training, but I do. I've now got a shape I've never had before.
"I feel camera-ready for future projects and for my little girl - who you've got to have a lot of energy for."
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