The Intermediate-Range Nuclear Forces -- or INF -- treaty -- stops America and Russia from having, making or testing ground-based cruise missiles that can be fired from 300 to 3400 miles. When it was signed, it was seen as a very important step in improving ties between the US and the Soviet Union.
“This treaty was one of the most successful elements of arms control that was introduced in the late Cold War, and it was actually one of few treaties to have survived until now,” said Keir Giles, an expert on Russian defence and security at Chatham House in London, in an interview with RFI.
Ex-Soviet leader Mikhail Gorbachev, who signed the INF deal with then US President Ronald Reagan in 1987, says Trump's plan to quit the deal shows a "lack of wisdom".
However, in 2017, US officials said Russia had broken the treaty's terms by testing a banned cruise missile. It's not just the Trump White House that's said this - the Obama administration accused Moscow of the same thing in 2014.
“Russia has been producing weapons that aren’t treaty-compliant, so the pressure has been growing,” Giles continued. “Throughout Obama’s last term there were increasingly calls to recognise the fact that Russia was not in compliance with the treaty and apparently had no intention of being so.
The further issue is that this was a bilateral treaty, so it did not contain, say, China. And now that the US sees China as a major competitor in military as well as economic terms, that too calls into question the agreement’s validity.”
Many analysts have said that Russia might be emboldened to ramp up its production and testing of cruise missiles without the INF treaty holding it back.
But others have argued that - with an economy smaller than Italy's - Russia effectively lack the means to take part in an arms race.
“Russia cannot afford to build up its defensive and offensive capacities to the same extent that the US does,” Derek Averre, a Russian military and defence specialist at Birmingham University, told RFI.