Russian President Vladimir Putin signed a bill on Tuesday suspending the country's last nuclear arms treaty with the US, known as the New START treaty.
Putin declared in a national address last week that he would put the agreement on hold. The deal limits the number of nuclear warheads, missiles and bombers in each country's arsenal.
Russian officials said they will not rejoin the treaty until the US starts listening to their concerns.
Russian Presidential spokesperson Dmitry Peskov said, "The countries of the collective West, led by the United States of America, must change their understanding of our country's concerns about security."
US President Joe Biden said Putin is making a "big mistake." However, officials in his administration say they will keep working with their Russian counterparts to implement the treaty.