The Discovery Communications headquarters building is seen in Silver Spring, Maryland December 3, 2009. REUTERS/Brad Bower/File Photo

(Reuters) - Discovery Communications Inc’s UK unit said on Wednesday negotiations with Sky Plc for a new carriage deal reached an impasse over a price dispute, threatening a blackout of Discovery channels from Sky’s platform.

All 12 channels in the Discovery portfolio would disappear from Sky and NOW TV after Jan. 31 if the dispute is not resolved, affecting more than 5.5 million people, Discovery Networks UK and Ireland said in a statement.

Sky finds the price expectations for the Discovery portfolio to be “completely unrealistic”, a representative for the pay-TV company said. “Discovery’s portfolio of channels includes many which are linear-only where viewing is falling.”

“We have been overpaying Discovery for years and are not going to anymore.”

Sky has decided not to renew it’s contract on the terms offered by Discovery, the representative added.

Discovery, which has TLC, Animal Planet, and Eurosport in its portfolio, said it is now paid less by Sky than it was 10 years ago.