Minogue was in negotiations to reprise her role on the show after last year's panellist Kelly Rowland ruled herself out.
The Australian entertained the idea of a return despite disclosures that she and show boss Simon Cowell had an affair. But discussions have now foundered.
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Showers becoming heavy and thundery this afternoon with sunny spells in between. Breezy along the coast.
Sunny spells and heavy thundery showers this afternoon.
Weight of people trying to sign caused government petition to website to crash as Europhiles try to force a rerun of the EU vote.