Usher and Shakira are set to replace Christina Aguilera and Cee Lo Green on The Voice. The pair were recruited to join the fourth season of the singing show after Christina decided to leave to spend time touring and promoting her new album Lotus while Cee Lo is working with NBC on a new show of his own. However, they will both return for season five.

"Doing two back-to-back cycles of this show requires a tremendous amount of time, and we are happy to accommodate the commitments made by Christina and Cee Lo. The participants on our show benefit from our coaches' expertise and their continued success in the music business allows for significant new contributions to the contestants when they return," said chairman of NBC Entertainment Robert Greenblatt.

Original coaches Adam Levine and Blake Shelton will remain on the panel.

Christina recently complained she has no "free time" due to The Voice's success. The singer admitted she only took the job initially because it meant she could be close to her four-year-old son Max, and was not expecting it to be as big as it has become: "I thought, 'It'll keep me close to my son Max in Los Angeles. I don't have to travel. Then it kind of took off and there goes my free time!"