U.S. Secretary of State Mike Pompeo has announced the United States will suspend its obligations under the Intermediate-Range Nuclear Forces (INF) Treaty as of February 2.
Speaking on February 1, Pompeo said Washington will formally notify Moscow that the United States is withdrawing from the INF Treaty in six months.
"For years, Russia has violated terms of the INF Treaty without remorse," Pompeo said. "To this day, Russia remains in material breach of obligations."
"The United States will therefore suspend its obligations under the INF Treaty effective February 2," Pompeo said. "We will provide Russia and the other treaty parties with formal notice that the United States is withdrawing from the INF Treaty effective in six months, pursuant to Article 15 of the treaty."
Moscow denies it has violated the treaty and has called on Washington to offer proof of its allegations.
Shortly after Pompeo's announcement, U.S. President Donald Trump issued a written statement saying: "we will not remain constrained by its terms while Russia misrepresents its actions. We cannot be the only country in the world unilaterally bound by this treaty, or any other."
Trump added that Washington "will move forward with developing our own military response options and will work with NATO and our other allies and partners to deny Russia any military advantage from its unlawful conduct."
Pompeo told reporters in Washington that the United States remained open to arms-control negotiations with Russia.
He said U.S. President Donald Trump wanted an agreement that is verifiable and enforceable.
Pompeo said the United States had gone to "tremendous lengths" over nearly six years to save the treaty and that the issue had been discussed, including "at the highest levels," more than 30 times.
Minutes after Pompeo's expected announcement, NATO allies issued a statement saying they "fully support" the U.S. decision to withdraw from the INF Treaty.
German Foreign Minister Heiko Maas urged Russia to "restore confidence" in the treaty, writing on Twitter "there will be less security without the treaty."
The U.S. action has been expected for months and was virtually assured after last-ditch talks in Beijing on January 31 between Russian Deputy Foreign Minister Sergei Ryabkov and U.S. Undersecretary of State Andrea Thompson ended without agreement.
"Unfortunately, there is no progress," Russian news agencies quoted Ryabkov as saying after the talks with Thompson.
In an interview with Reuters, Thompson said, "The Russians still aren't in acknowledgment that they are in violation of the treaty."
The fate of the 1987 INF Treaty, widely seen as a cornerstone of arms-control stability in Europe and elsewhere, has been a source of tensions between Moscow and Washington.
Washington and NATO accuse Russia of breaching the treaty by developing the 9M729 cruise missile, also known as the SSC-8.
Moscow denies that the missile violates the INF Treaty and accuses the United States of seeking to abandon the pact so it can start a new arms race.
The Wall Street Journal on January 31 quoted Western officials as saying Russia had deployed four battalions of the 9M729 cruise missile, up from the three battalions Russia was said to have a few months ago.
The 1987 treaty prohibits the two countries from possessing, producing, or deploying ground-launched cruise or ballistic missiles with ranges between 500 and 5,500 kilometers. The agreement was the first of its kind to eliminate an entire class of missiles.
The United States first publicly accused Moscow of violating the INF Treaty in 2014. After several years of fruitless talks, Washington began stepping up its rhetoric in late 2017, publicly identifying the missile in question and asserting that Russia had moved beyond testing and had begun deploying the systems.
Late last year, Washington began providing NATO members and other allies with more detailed, classified satellite and telemetry data, as part of the effort to build support for its accusations.