On its Facebook page, the Russian embassy in the US said it took the move to mean that the United States is pursuing a "path of conscious deterioration of relations", and that it considers the registration requirement to be "a desire to eliminate the source of alternative information, an unacceptable violation of global standards of press freedom".
"It deprives us of fair competition with other worldwide channels, which are not registered as foreign agents", she was quoted as saying by RT.
Russian news media and social media actors have come under scrutiny after USA intelligence agencies concluded in January that Russia sought to interfere with the US presidential election to help Donald Trump win.
This is not the first time Russian Federation has criticized the US for taking actions against its media outlets.
Reuters reported that Russian lawmakers said "the move was retaliation for a demand by the U.S. Department of Justice that Kremlin-backed TV station RT register in the United States as a "foreign agent", something Moscow has said it regards as an unfriendly act". "Our lawyers say that if we don't register as a foreign agent, the director of our company in America could be arrested, and the accounts of the company could be seized".
RT began operations in 2005 under the brand Russia Today, claiming to present the Russian view on global news and to cover stories ignored by mainstream Western news media.More news: Queen's private estate 'invested millions of pounds in offshore tax havens'
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USA government-sponsored Radio Free Europe/Radio Liberty (RFE/RL) said last month Moscow had threatened to brand their Russian language service projects "foreign agents" in retaliation for US pressure on RT.
"The Russian side has repeatedly warned that any measures limiting activity of the Russian mass media in the United States will inevitably trigger an immediate symmetrical response", the Russian embassy posted.
The Russian law on foreign agents in recent years has been used on nongovernmental groups that do not toe the Kremlin party line.
An intelligence report in January alleged the outlet spearheaded "strategic messaging for [the] Russian government", fueling political conflicts in the US during the 2016 campaign.
The assessment also said RT America "has positioned itself as a domestic USA channel and has deliberately sought to obscure any legal ties to the Russian government, " but behind the scenes, "the Kremlin staffs RT and closely supervises RT's coverage, recruiting people who can convey Russian strategic messaging due to their ideological beliefs".