X-Factor judge Dannii Minogue quits show 'because she can't fit it into her schedule'
The 39-year-old singer has parted company with the popular ITV talent contest days before the new series was due to launch.
She posted a link through Twitter to a website which she is a contributing editor to, confirming the news.
'I'm going to miss the show and the amazing team who work so incredibly hard on it.'
X-Factor judges Cheryl Cole and Simon Cowell have already quit to take part in the U.S. version of the show - although Cowell will be a huge presence behind the scenes in the UK - and Take That's Gary Barlow has been lined up as a replacement.
Kylie's sister began filming the fifth series of Australia's Got Talent at the start of the year and is scheduled to return in a couple of weeks to continue with the semi and grand finals.
'For this reason I am unable to return. I want to wish the new judges every success for this year's show, and can't wait to see who the British public choose as their next big star.
'Thanks to everyone who has shown me so much love and support, and brought me so much joy during my four incredible years working on the show.'
Dannii started on the X Factor in 2007 but revealed in her autobiography last year that she was made to feel undermined by former judge Sharon Osbourne who resente3d her being there.
The move is not connected with Minogue's departure however, the source stressed.
He said: 'Everyone on the show has met her, and they loved her. She's the real deal. She's not a reality TV creation, she's created herself.'
The singer from north London also fits 'the right age demographic', he added.