(Image Credit: Mark J. Terrill/AP Photo)

Keith Olbermann has threatened to sue Current TV after the controversial host was fired from his primetime slot less than a year after he joined the network.

Former Vice President Al Gore, the co-founder of Current TV, said in a statement that the network was founded on "values of respect, openness, collegiality and loyalty to our viewers. Unfortunately these values are no longer reflected in our relationship with Keith Olbermann."

Not one to go down without a fight, Olbermann fired back on Twitter, writing that the accusations were "untrue and will be proved so in the legal actions I will be filing against them presently."

Gore's stark language in severing ties with Olbermann less than a year after the dream deal stunned media observers.

"It's surprising to watch Al Gore, who swore he knew how to handle Keith Olbermann, essentially throw in the towel and say he and Current TV don't line up anymore," Brian Stelter, a New York Times media writer, told ABC News.

The former host of "Countdown" on MSNBC, who was reportedly being paid $50 million for five years, was immediately replaced by former New York Gov. Eliot Spitzer, who took over the 8 p.m. slot with a show called "Viewpoint."