American Idol's Steven Tyler, Jennifer Lopez, Randy Jackson and Ryan Seacrest (Source: Kevin Winter, Getty)

The producers of American Idol have finally confirmed that Jennifer Lopez and Steven Tyler will be joining the popular talent show as members of its judging panel.

Following weeks of reports about imminent deals, the two singers were unveiled at a news conference on Wednesday as the new judges for the Fox series, which is entering its tenth season.

The pair will replace Simon Cowell, Ellen DeGeneres and Kara DioGuardi on the panel, all of whom announced their departures in recent months. Randy Jackson is the only judge remaining from the show's first series; Ryan Seacrest will continue to host the programme.

Lopez, 41, has had a successful career in music, television and film; her latest album, entitled Love?, is scheduled for release later this year. She was reportedly enticed with a one-year contract worth $US12 million ($A12.5 million).

"I kind of raised my eyebrows [at the prospect of judging on American Idol], but my career has always been the type that changes and evolves," she said at the news conference.

Lopez and the show's producers sought to stamp out reports that her "diva demands" had held up attempts to strike a deal, saying that the protracted negotiations process was par for the course. Some sources had claimed that Fox executives had ended talks with Lopez due to the continued delays.

"It was all about schedule and dates. They were typical deals, to be frank," said Mike Darnell, Fox's president of alternative programming.

Tyler, the controversial lead singer for the rock band Aerosmith, said that he was a fan of the series and hoped to bring "some rock to this rollercoaster".

"I want to give everybody a little love before I decide who goes home heartbroken. If you don't like what I say, don't get mad, get better," the 62-year-old said.

Idol overhaul

Jimmy Iovine, the record executive (Source: Albert L. Ortega)

The additions of Lopez and Tyler confirm producers' intentions to restore a three-person judging panel - there are no plans for guest-judging roles - and will be accompanied by further changes to the show's format.

Fox announced that Jimmy Iovine, the chairman of the Interscope-Geffen-A&M record label, would be taking on a prominent role as a permanent "mentor" on the programme, working extensively with contestants and helping to promote their talents in the industry.

The centrality of Iovine's role will effectively push out existing elements of the programmes: genre-themed weeks and guest mentors are set to disappear. The show's producers also suggested that contestants would have to incorporate more movement on the stage, rather than harnessing only their vocal skills.

Plans for an on-air shake-up have unfolded alongside major changes behind the scenes. Nigel Lythgoe, who served as the programme's executive producer for six years, returned to the role last month and flagged his intention to push for drastic steps to arrest a decline in the series' popularity.

"We are ten years old, and we are being given the opportunity to recreate the magic," Lythgoe said.

The tenth season of American Idol is due to return in January 2011.

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