Simon Cowell says 'The Voice' and NBC are 'cynical, cold-hearted, unprofessional'

Simon Cowell has some harsh words for NBC's "The Voice," after the reality singing competition added a Wednesday episode during next week's premiere week, which will overlap with the first hour of the "X Factor" premiere.

"This is a cynical, cold-hearted, unprofessional way of doing business," Cowell tells TMZ. He adds he thought he had a "gentleman's agreement" with NBC, wherein "The Voice" runs Mondays and Tuesdays and "X Factor" runs Wednesdays and Thursdays so that fans can watch both.

"Britney's not going to appreciate the fact that Christina -- who has been a bit of a rival -- isn't allowing Britney to have a night of her own," adds Cowell.

"These guys have really got it in for us.  It's nothing short of dirty tricks. The reason they've done this is they don't want people to see 'X Factor' because they've heard how good the series is. They don't want their audience to see Britney Spears. They don't want their audience to see Demi Lovato," Cowell continues. "I can't bear it that the network is playing political games and playing with the audience."