Russian President Vladimir Putin has threatened to build new missiles after the US suspended a nuclear pact between the countries.
It comes after US secretary of state Mike Pompeo announced on Friday that he was suspending compliance with the treaty, which was signed towards the end of the Cold War by presidents Mikhail Gorbachev and Ronald Reagan.
The Intermediate-Range Nuclear Forces (INF) bans ground-launched missiles with a range between 500 and 5,500km.
Western experts say the new Russian medium-range missile system is in breach of the agreement.
The Trump administration announced it was suspending compliance with the pact for six months and that it would withdraw completely unless Russia changed course.
Russia’s response has been to also suspend its participation in the treaty for six months – and state that, like the US, it was prepared to withdraw in six months.
Mr Putin also suggested his military would start working on new weapons, including supersonic missiles.
He met with foreign and defence ministers to tell them not to initiate disarmament talks with the White House.
Mr Putin said: “Our American partners have announced they are suspending their participation in the deal, and we are also suspending our participation.
“We will wait until our partners have matured enough to conduct an equal, meaningful dialogue with us on this important topic.
“They have announced they will conduct research and development, and we will act accordingly.”
He said Russia would not deploy intermediate-range missiles unless the US did and would not be drawn into a costly new arms race.
He added: “We have repeatedly, during a number of years, and constantly raised a question about substantive talks on the disarmament issue, notably, on all the aspects.
“We see that in the past few years the partners have not supported our initiatives.”
Foreign minister Sergey Lavrov said the White House had ignored Russia’s offer to inspect the cruise missile that has caused the dispute.
He also accused the US of violating the pact by deploying missile interceptors in Romania that use launchers that could hold land-based cruise missiles.
Mr Lavrov said another arms pact, the New Start, which is due to expire in 2021, could also be suspended.
NATO has already said it “fully supports” the US, adding: “Allies regret that Russia, as part of its broader pattern of behaviour, continues to deny its INF Treaty violation, refuses to provide any credible response, and has taken no demonstrable steps toward returning to full and verifiable compliance.”
China’s government appealed to both nations to maintain the treaty.
The country’s foreign ministry warned there could be “adverse consequences” after the Trump administration withdrew.
A ministry statement said: “China is opposed to the US withdrawal and urges the US and Russia to properly resolve differences through constructive dialogue.”
(c) Sky News 2019: Vladimir Putin threatens new missiles after US suspends nuclear pact