It is reported that Mariah Carey is in final negotiations to mentor Simon Cowell's acts on The X Factor USA.
Deadline.com, which broke the story, quotes a source as saying: "He's [Cowell] still finalising her deal."
The source added that contracts were being drawn up with "the Beyoncés, the Rihannas, all of them" as the show adds more stars to its line-up.
The series begins on American television on September 21.
