President Donald Trump announced Thursday he plans to withdraw the United States from the Open Skies Treaty with Russia, the third arms control pact Trump has abrogated since coming to office.
The US leader said Moscow had not stuck to its commitments under the 18-year-old pact, which was designed to improve military transparency and confidence between the superpowers.
"Russia did not adhere to the treaty," Trump told reporters at the White House.
"So until they adhere, we will pull out."
The New York Times reported that Trump plans to inform Moscow of the move on Friday, and that it could be a prelude to Washington also withdrawing from the New START Treaty, which limits the number of nuclear missiles the United States and Russia can deploy.
The Open Skies agreement between Russia, the United States and 32 other countries, mostly members of the NATO alliance, permits one country's military to conduct a certain number of surveillance flights over another each year on short notice.
The aircraft can survey the territory below, collecting information and pictures of military installations and activities.
The idea is that the more rival militaries know about each other, the less the chance of conflict between them.
But the sides also use the flights to examine vulnerabilities of their opponent.
The United States has been frustrated that Russia will not permit US flights over areas where Washington believes Moscow is deploying medium-range nuclear weapons that threaten Europe.
Pentagon spokesman Jonathan Hoffman said Russia "flagrantly, continuously violates its obligations" under the pact.
Moscow "implements the treaty in ways that contribute to military threats against the United States and our allies and partners," he said.
He cited Russia's refusal to allow flights over areas where Washington believes Moscow is deploying medium-range nuclear weapons, including the Baltic Sea city of Kaliningrad and near the Russia-Georgia border.
Last year Moscow also blocked flights meant to survey Russian military exercises, normally allowed under the pact.
The New York Times said Trump was also unhappy about a Russian flight over his golf resort in Bedminster, New Jersey three years ago.
"In this era of great power competition, we are looking to advocate for agreements that benefit all sides, and that include partners who comply responsibly with their obligations," Hoffman said.
Since coming to office in January 2017, Trump has withdrawn from two other major arms control pacts, the 2015 JCPOA agreement to prevent Iran from advancing its nuclear weapons program, and the 1988 Intermediate Range Nuclear Forces Treaty with Russia.
In both cases Trump accused the other side of violating treaty requirements.