Nick Cannon says he’s leaving as host of NBC’s America’s Got Talent after he learned network execs were considering firing him over a racial joke he told in his Showtime comedy special. Stand Up, Don’t Shoot, described as a stand-up special in which Cannon takes on race and other topics, premiered Friday, February 10 on Showtime.

“After days of deliberating over some extremely disappointing news that I was being threatened with termination by Executives because of a comedy special that was only intended to bring communities closer together, I was to be punished for a joke,” he writes on Instagram and Facebook. “This has weighed heavy on my spirit. It was brought to my attention by my “team” that NBC believed that I was in breach of contract because I had disparaged their brand. In my defense, I would ask how so? Or is this just another way to silence and control an outspoken voice who often battles the establishment.”