The Kremlin-backed channel said yesterday the Department of Justice had given it until Monday to register its US operations as a foreign agent or see its head arrested and its accounts frozen.
RT head Margarita Simonyan called the US deadline "cannibalistic" and said the channel would comply with the demand but will go to court.
"We believe that the demand does not only go against the law, and we will prove it in court -- the demand is discriminative, it contradicts both the democracy and freedom of speech principles," Simonyan was quoted as saying by RT.
"It deprives us of fair competition with other international channels, which are not registered as foreign agents," she added.
She said the channel would comply to keep its assets and continue broadcasting in the United States.
"The US Department of Justice wheeled out a cannibalistic Monday deadline," she tweeted Thursday. "Can you feel the smell of freedom?" she said caustically.
Washington sees RT as Moscow's propaganda arm and has asked RT to register its American operations as a "foreign agent" under the Foreign Agents Registration Act, an act aimed at lobbyists and lawyers representing foreign political interests.
The Moscow-based broadcaster has become a focus of the investigations into alleged Russian interference in the 2016 US presidential election.
RT has been singled out for its links to President Donald Trump's discredited former national security advisor Michael Flynn.
Flynn, the former US defence intelligence chief, was paid tens of thousands of dollars in December 2015 to attend an RT anniversary gala where he sat with Russian President Vladimir Putin.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)