Cee Lo Green has been performing with Rihanna on her Loud tour and together they have visited at least 17 cities. Now, to the disappointment of Cee Lo fans, he will be pulling out of the tour.

"He always puts 100 percent into his work," says a spokesperson for Cee Lo. "And with the requirements and time commitment to 'The Voice,' on top of heading back into the recording studio and an upcoming book, he feels that he wouldn't give his fans the show that they deserve."

The artist does have a lot on his plate. Despite the fact that "The Voice" only has one more week to go, he's going back into the studio with Gnarls Barkley, as previously reported, and the collaborations and complicated alt-pop that is Gnarls will be an extremely time consuming venture. No word as of yet on where he is with his book, but no doubt it will be as groundbreaking as his musical efforts.