The US has formally withdrawn from a key nuclear treaty with Russia, raising fears of a new arms race.
The Intermediate-Range Nuclear Forces Treaty (INF) was signed by US President Ronald Reagan and Soviet leader Mikhail Gorbachev in 1987.
It banned missiles with ranges between 500 and 5,500 km (310-3,400 miles).
But earlier this year the US and Nato accused Russia of violating the pact by deploying a new type of cruise missile, which Moscow has denied.
The Americans said they had evidence that Russia had deployed a number of 9M729 missiles – known to Nato as SSC-8. This accusation was then put to Washington’s Nato allies, which all backed the US claim.
“Russia is solely responsible for the treaty’s demise,” Secretary of State Mike Pompeo said in a statement on Friday.
“With the full support of our Nato allies, the United States has determined Russia to be in material breach of the treaty, and has subsequently suspended our obligations under the treaty,” he added.
Russia’s foreign ministry confirmed the INF treaty was “formally dead” in a statement carried by state-run Ria Novosti news agency.
Back in February, President Donald Trump set the 2 August deadline for the US to withdraw if Russia didn’t come into compliance.
Russian President Vladimir Putin suspended his country’s own obligations to the treaty shortly afterwards.
What are the risks?
Nato Secretary General Jens Stoltenberg said the transatlantic alliance would “respond in a measured and responsible way to the significant risks posed by the Russian 9M729 missile to allied security”.
But, he added, Nato “does not want a new arms race” and confirmed there were no plans for the alliance to deploy land-based nuclear missiles of its own in Europe.
Last month, he told the BBC that the Russian missiles were nuclear-capable,mobile, very hard to detect and could reach European cities within minutes.
“This is serious,” he added. “The INF treaty has been a cornerstone in arms control for decades, and now we see the demise of the treaty.”
UN Secretary General Antonio Guterres has warned that “an invaluable brake on nuclear war” was being lost.
“This will likely heighten, not reduce, the threat posed by ballistic missiles,” he added, urging all parties to “seek agreement on a new common path for international arms control”.