Russian President Vladimir Putin signed a law Tuesday that formally suspends Russia's participation in the New Strategic Arms Reduction Treaty (START).
"The Russian Federation suspends the Treaty between the Russian Federation and the United States of America on measures for the further reduction and limitation of strategic offensive arms, signed in Prague on April 8, 2010," the text of the law's explanatory note said.
Putin said last week that Russia was suspending participation in the Strategic Arms Reduction Treaty, but it was not withdrawing from it.
Russia’s Foreign Ministry also said Moscow will continue to respect the caps established in the treaty and reiterated that Putin’s suspension of the treaty is “reversible.”
The Russian president is the one who can make the decision to resume the country's participation in the agreement.
Some context: The treaty is the last in a long series of nuclear treaties between the US and Russia, previously the Soviet Union. It puts limits on the number of deployed intercontinental-range nuclear weapons that both the US and Russia can have. It was last extended in early 2021 for five years, meaning the two sides would soon need to begin negotiating on another arms control agreement.
The treaty was already essentially paused since Russia had recently refused to open up its arsenal to inspectors.
A top US State Department official said Monday that the United States "very much" hopes Russia is still interested in arms control, but Putin's decision to suspend New START participation calls the interest into question.
“By tying it to Ukraine right now, tying it to an immovable object in the sense that our support for Ukraine will not be limited by their New START decision, they’re really placing in doubt their support for the treaty itself,” Assistant Secretary for the Bureau of Arms Control, Verification, and Compliance Mallory Stewart said.
CNN's Jennifer Hansler, Rob Picheta, Anna Chernova, Nathan Hodge, Lauren Kent and Radina Gigova contributed to this post.