Although it was thought that Jackson - who has been on the panel of the show since it began - would take on the role of a "mentor" behind the scenes for the upcoming season, he has agreed a deal with Fox to stay on as a judge after negotiations with Enrique Iglesias fell though, according to Deadline.

Appearing to confirm the news, his former co-star Simon Cowell tweeted: "Just heard Randy is back on Idol. Right decision."

Jackson will join Mariah Carey on the four person panel which is also expected to feature Keith Urban and Nicki Minaj.

Carey is not thought to be a fan of Minaj’s, although producers are delighted at the prospect of conflict between them both.

Instead the Fantasy hitmaker is said to be keen for Lenny Kravitz to sign up to the show.

A source said recently: "Mariah would love to have her dear friend Lenny Kravitz sit next to her on the 'American Idol' judge panel. She thinks he would be the perfect choice because he is extremely talented and knows music inside and out."

Watch the last season's Idol Top 10 'singing the phonebook' in honour of Randy Jackson's favourite compliment: