Olbermann's nightly commentary show, "Countdown with Keith Olbermann," premiered in June on Current TV. He also was appointed the network's chief news officer after he left MSNBC in January 2011 following stormy interactions with management, including a suspension for contributing to political candidates.
His MSNBC show also was called "Countdown with Keith Olbermann."
"I'd like to apologize to my viewers and my staff for the failure of Current TV," Olbermann said in a statement on Twitter after the network had announced his firing on its Web site.
"Editorially, 'Countdown' had never been better. But for more than a year, I have been imploring (Current owners) Al Gore and Joel Hyatt to resolve our issues internally, while I've been not publicizing my complaints, and keeping the show alive for the sake of its loyal viewers and even more loyal staff," Olbermann wrote. "Nevertheless, Mr. Gore and Mr. Hyatt, instead of abiding by their promises and obligations and investing in a quality news program, finally thought it was more economical to try to get out of my contract.
"It goes almost without saying that the claims against me implied in Current's statement are untrue and will be proved so in the legal actions I will be filing against them presently. ... For now, it is important only to again acknowledge that joining them was a sincere and well-intentioned gesture on my part, but in retrospect a foolish one. That lack of judgment is mine and mine alone, and I apologize again for it."
Gore and Hyatt said in their statement Current TV was "founded on the values of respect, openness, collegiality, and loyalty to our viewers."
"Unfortunately, these values are no longer reflected in our relationship with Keith Olbermann and we have ended it," they added. "We are moving ahead by honoring Current's values. Current has a fundamental obligation to deliver news programming with a progressive perspective that our viewers can count on being available daily -- especially now, during the presidential election campaign. Current exists because our audience desires the kind of perspective, insight and commentary that is not easily found elsewhere in this time of big media consolidation."
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