The US is poised to increase its stock of intermediate missiles as the country formally pulled out of a long-standing nuclear treaty on Friday.
The move – which had been flagged earlier this year – sees the US leave the Intermediate-range Nuclear Forces (INF) treaty, which was signed in 1987 by US president Ronald Reagan and Soviet leader Mikhail Gorbachev.
The US warned it would pull out of the deal alleging Russian non-compliance. The move is seen by some as an effort by the US to free itself from the limits of the agreement in order to counter the rising threat of China.
The Pentagon is expected to test a ground-launched cruise missile in the coming weeks, and test an intermediate-range ballistic missile before the end of the year.
The United Nations said that the world had lost "an invaluable brake on nuclear war" with the expiry of the agreement.
"This will likely heighten, not reduce, the threat posed by ballistic missiles," UN secretary general Antonio Gutteres said.
Russia said the treaty had been dismantled "at the initiative of the United States".
The cold war-era treaty banned all nuclear and conventional ground-launched ballistic and cruise missiles between the ranges of 500km and 5,500km. Thousands of missiles were destroyed under the agreement.
However, the Trump administration said six months ago that it would reassess its compliance with the agreement because Russia had developed a land-based nuclear-capable cruise missile, which violated the accord.
"Russia is solely responsible for the treaty's demise," secretary of state Mike Pompeo said in a statement on Friday.
Nato said it fully supported the US in its decision. "Russia bears sole responsibility for the demise of the treaty," said secretary general Jens Stoltenberg. "We regret that Russia has shown no willingness and taken no demonstrable steps to return to compliance with its international obligations. A situation whereby the United States fully abides by the treaty and Russia does not is not sustainable."
Sanctions
The move comes as Washington imposed a new round of sanctions on Russia over the poisoning of former spy Sergei Skripal in Britain last year.
Meanwhile, there were reports that the US is close to a deal with the Taliban in Afghanistan, which would see as many as 5,000 US troops withdraw from the country.
President Donald Trump pledged to end the US's involvement in the 18-year conflict when he was elected, but approximately 14,000 troops remain in the country.
Under the deal the Taliban would begin negotiating a deal directly with the Afghan government and would be forced to denounce terror group al-Qaeda.
Mr Trump raised the issue of Afghanistan during a campaign rally in Cincinnati on Thursday night, when he quipped that the crime rate was lower there than in the US city of Baltimore.
Mr Trump has been attacking the Democratic political leaders of American cities in recent days. On Friday, responding to news that the home of C+ongressman Elijah Cummings in Baltimore had been burgled, Mr Trump tweeted: "Really bad news! The Baltimore house of Elijah Cummings was robbed. Too bad!"
His tweet prompted a rare rebuke from former US ambassador to the UN Nikki Haley, who tweeted: "This is so unnecessary."
