The U.S. State Department has accused Russia of breaching a critical nuclear arms treaty by refusing to allow inspections of its territory.

The treaty, called the New Strategic Arms Reduction Treaty or New START, is the only form of control of the world’s largest stocks of nuclear weapons.

Russia threatened to use nuclear weapons to defend Ukraine in October. Western leaders say the danger of those threats has diminished since then, according to The Washington Post, but they may be cause for concern once again considering Russia’s alleged noncompliance.

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What is New START?

New START is one of the last remnants of the Cold War, the peak of the U.S. and Russia’s tension concerning nuclear arsenals. The two countries now own about 90% of the world’s nuclear weapons, according to Reuters.

Signed by former President Barack Obama and former Russian President Dmitry Medvedev in 2010, the treaty holds both countries to a series of agreements concerning their nuclear arsenals.

Among these agreements are limits on the number of nuclear weapons, data exchanges, onsite inspections and regular meetings to ensure compliance.

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In 2021, the U.S. and Russia agreed to extend the treaty to February 2026. Russia, however, has not facilitated an inspection for three years, at first because of the COVID-19 pandemic, but then because of the deteriorating relationship between the two countries, The Washington Post reported.

Russia restricted American inspectors from accessing its nuclear arsenal last August in response to U.S.-imposed travel restrictions, according to Reuters, but said it would continue to observe other agreements within New START. In November, Russia postponed a meeting about the treaty.

Russia’s response to U.S. accusations

Russia rejects the allegations of noncompliance, The Moscow Times reported, saying the U.S. is at fault for weakening the treaty.

“Responsibility for the escalation of the New START issues lies entirely with Washington,” Ambassador Anatoly Antonov said. “There can be no progress on arms control without the United States reconsidering its policy of inflicting strategic defeat on Russia.”

The ambassador even accused the U.S. of breaching the pact with “the illegitimate removal of more than a hundred strategic weapons from the accountability under the treaty.”

Kremlin spokesman Dmitry Peskov described the treaty as “very important” and “at least hypothetically viable,” per Reuters, but that ultimately the U.S. deserves the blame for agreements’ deterioration.

Russia has expressed the possibility that there will be no new treaty to control nuclear arms after New START expires.

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