Simon Cowell: Judging on "American Idol" may be hard for Mariah Carey

(CBS News) After the news was made official that Mariah Carey would join "American Idol" as a judge, Simon Cowell told the audience at a Television Critics Association (TCA) panel for the "X Factor" that he is not sure if she'll be able to handle sending "Idol" hopefuls home.

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"I think she's going to fit it difficult to say 'no' [to contestants]," Cowell told reporters via satellite, according to Entertainment Weekly. "She's sweet."

Cowell also had things to say about his fellow "X Factor" judges, calling Britney Sears "quite mean" and Demi Lovato "a brat."

Lovato teased Cowell, saying, "You're not going to gang up - you're going to have two girls --" and Cowell interjected that he had had enough, EW reports.

Fox announced Monday that Carey would join the "Idol" judges' panel for the show's 12th season.

Earlier this month, Steven Tyler and Jennifer Lopez said they were leaving "American Idol" after two years as judges.