The 1987 Intermediate-Range Nuclear Forces (INF) Treaty was signed by Ronald Reagan and Mikhail Gorbachev to ban American and Soviet land-based ballistic and cruise missiles with a range of 310-3420 miles. The US considered 12 post-Soviets, all except the Baltic nations, to be bound to the treaty obligations. Russia, Belarus, Kazakhstan, Ukraine, Turkmenistan and Uzbekistan all had significant sites that would be inspected according to the treaty.
President Trump said in October Russia had been reneged on the treaty in secret and the US would withdraw.
The process started in February and Mr Putin started his withdrawal the next day in response.
Mr Trump’s team said Russia’s deployment of the Novator 9M729 land-based cruise missile broke the treaty, with the POTUS saying Russia had been “violating for many years.”
The administration of Barack Obama, according to Fox, felt the treaty was being violated in 2012 but did not inform all of NATO.
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At a Nevada rally, Mr Trump questioned why Mr Obama had not taken a hawkish response to developments: “We’re not going to let them violate a nuclear agreement and go out and do weapons, and we’re not allowed to.”
Top Russian officials said the remarks were “very dangerous” and could lead to “full chaos”.
NATO Secretary General Jens Stoltenberg agreed with the American leader however: “After years of denials, Russia recently acknowledged the existence of a new missile system, called 9M729, Russia has not provided any credible answers on this new missile. All allies agree that the most plausible assessment would be that Russia is in violation of the treaty.”
By June 1 1991 under the terms of the INF treaty the Soviet had destroyed 1,846 weapons and the US 846.
Inspections were taken until 2001 and since satellites have been used to verify compliance.
Russia has accused the US of using European allies to bypass the treaty thought the backdoor and Mr Putin said at a Munich Conference in 2007 the treaty was flawed as it only bounded Russia and the US and not other countries.
Mr Gorbachev has criticised Mr Trump for the withdrawal saying it was “not the work of a great mind” and that “a new arms race has been announced”.
The signing of the INF Treaty was in doubt after talks in Reykjavik between Mr Gorbachev and Mr Reagan initially collapsed at the last minute.