Nicki Minaj and Mariah Carey have quit 'American Idol'.

The 'Starships' hitmaker and the 43-year-old superstar announced they were leaving the show as judges within hours of one other last night (30.05.13), claiming they want to focus on their music careers.

Nicki took to Twitter to thank the show for her success, writing: ''Thank you American Idol for a life changing experience! Wouldn't trade it for the world! Time to focus on the Music!!! Mmmuuuaahhh!!! (sic).''

Hours before Nicki announced her departure from 'Idol', Mariah confirmed she had abandoned the show after just one season in order to embark upon a world tour, following the success of her latest single 'Beautiful'.

Mariah retweeted a message from her PR representatives which read: ''W/ global success of ''#Beautiful'' (#1 in 30+ countries so far) @MariahCarey confirms world tour & says goodbye 2 Idol (sic).''

Aside from her tour, Mariah has a number of other exciting projects lined up this year.

Her representative told People magazine: ''The rest of this year is jam-packed with Mariah putting the finishing touches on her much anticipated forthcoming album, headlining Macy's 4th of July Fireworks Spectacular and appearing in Lee Daniels's 'The Butler', opening in August.''