MOSCOW -- President Vladimir Putin Monday (March 4) officially suspended Russia's participation in a key Cold War-era arms treaty, the Intermediate-Range Nuclear Forces (INF) Treaty.
Putin signed an executive order suspending Russia's compliance under the treaty, according to an English-language Kremlin statement.
After years of formal complaints and attempts at diplomatic resolution, the United States and NATO Allies concluded that Russia "openly violates" the landmark Cold War treaty.
Washington has been pointing out INF violations by the Kremlin since 2013, according to the US State Department, which cited the violations in annual reports of 2014 through 2018.
US President Donald Trump said in February that Washington would start a process to withdraw from the deal within six months.
"We're the ones who have stayed in the agreement, and we've honoured the agreement," Trump told reporters. "Russia has violated the agreement. They've been violating it for many years."
Putin responded soon after that Russia was planning to suspend its involvement and said the Russian military would begin developing medium-range missiles.
In his state of the nation address last month, delivered at a time of flagging popularity, Putin threatened to deploy new missiles against Western capitals.
Putin's speech mirrored the Kremlin's long-standing ploy of using an external threat to avoid dealing with domestic issues.
His tough military talk also seemed aimed at stirring up patriotic support at a time when the president's popularity is waning.
US Secretary of State Mike Pompeo dismissed the threats in Putin's state of the nation speech as "bluster" designed to divide Washington and its allies.
Any such efforts at division appear to have failed. In December, all 29 NATO foreign ministers issued a joint statement saying, "We strongly support the finding of the United States that Russia is in material breach of its obligations under the INF Treaty."
NATO has said that US allies "fully support" its withdrawal from the pact, insisting that Russia's 9M729 ground-launched cruise missile systems violate the treaty.
Brokered by then-US President Ronald Reagan and Soviet leader Mikhail Gorbachev, the INF Treaty ended a superpower buildup of warheads.
It banned ground-launched missiles with a range of 500 to 5,500km.
The deal addressed Soviet nuclear-tipped ballistic missiles targeting Western capitals but put no restrictions on other major military actors such as China.
European leaders have called on Russia to address concerns before the United States formally leaves in August.
Last week, United Nations Secretary-General António Guterres warned that "key components of the international arms control architecture are collapsing".
Another treaty's expiration is approaching.
The New Strategic Arms Reduction Treaty (START), which caps the number of nuclear warheads held by Washington and Moscow, expires in 2021.