Now magazine claims that Simon Cowell has tapped up the high-profile pop pair to replace departing judges Britney Spears and LA Reid.
The other panel members are SiCo himself and Demi Lovato.
A source said: "Simon sees it as a brilliant pairing. Katy's sassy, honest and a huge star, while John's more reserved.
"Having them as rivals would be genius - if they had on-air bust-ups, it'd be unmissable."
Perry was reported to have been one of SiCo's first choices for the show anyway.
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