It was not immediately known if he quit or was fired. Olbermann did not address the question, and MSNBC said only that they and Olbermann had ended their contract. He signed a four-year contract two years ago. "MSNBC thanks Keith for his integral role in MSNBC's success and we wish him well in his future endeavors," the network said.

A spokesman said Phil Griffin, MSNBC's president, would not comment on Olbermann's exit. Spokesman Jeremy Gaines would say only that the acquisition of NBC Universal by Comcast, which received regulatory approval this week, had nothing to do with the decision. Olbermann was suspended without pay from the network for two days in November for donating to three Democratic candidates, which violated NBC News' policy on political donations. Olbermann complained that he was being punished for mistakenly violating an inconsistently applied rule that he had known nothing about. The host apologized to fans - but not to the network.