R&B star Usher and Colombian singer Shakira have signed up to replace Cee Lo Green and Christina Aguilera on U.S. Tv talent show The Voice.

Green and Aguilera, who have coached wannabes on the series for the past two seasons, will leave the show in its upcoming fourth season.

Aguilera will be focusing on promoting her new album Lotus, while Green will be working on a new Tv sitcom project.

Usher and Shakira are being slated to play musical chairs with existing judges and coaches Blake Shelton and Adam Levine.

But Aguilera isn't planning to leave the show for good - she just wants to sit out a season and work on her solo career after releasing Lotus in November (12).

She recently told Billboard.com, "I'll probably be back. I just need to do my thing for a minute then I can come back and be that much better of a coach. I just need a second to get back to me."

The links to Usher and Shakira come just a day after Nicki Minaj and Keith Urban were confirmed as the judges who will join Randy Jackson and Mariah Carey on American Idol.

Meanwhile, Simon Cowell's The X Factor debuted last week (ends14Sep12) with new judges Britney Spears and Demi Lovato.