The Pentagon has played down claims by Russia that it is developing nuclear weapons that could strike anywhere in the world, sparking fears of an arms race.
In his annual state of the nation address on Thursday, Russian president Vladimir Putin said Moscow had been working "quietly and patiently" on a response to America's missile defence system.
Using elaborate video footage, Mr Putin devoted much of his speech to outlining how Russia had developed a nuclear-powered cruise missile capable of carrying a warhead over “practically unlimited range”.
He also described a “very threatening weapon” that could evade missile-detection systems by flying over the North and South Pole. Other systems Russia had developed included underwater drones and a hypersonic air-launched missile that could hit targets at 10 times the speed of sound, he said.
“Efforts to contain Russia have failed, face it,” Mr Putin said. “I hope that all that was said today will sober up any potential aggressor.”
‘Not surprised’
But the Pentagon sought to assuage fears about a nuclear threat from Russia. Speaking in Washington, Pentagon spokeswoman Dana White said: "We're not surprised by the statements, and the American people should rest assured that we are fully prepared."
Officials indicated that Russia's weapons had long been in development and were known to the United States.
Mr Putin’s comments came less than three weeks before Russia’s presidential election. He is campaigning to win a fourth six-year term, and is expected to win by a landslide.
Anti-corruption campaigner and opposition leader Alexei Navalny has been barred from standing in the election because of a criminal conviction that his supporters say was politically motivated. He was detained and released last week in Moscow. Among those running in the March 18th election are TV presenter Ksenia Sobchak and businessman Pavel Grudinin.
