Senior Russian security officials have launched diatribes at the West, accusing it of fomenting a new Cold War in a bid to retain waning influence in global affairs.
Moscow used an annual security conference attended by top officials from Asia, Africa and Latin America to criticise the US and its allies, accusing them of putting global stability at risk.
Defence minister Sergei Shoigu accused the US and Nato allies of using "the non-existent Russian threat to methodically boost their military potential" and beef up their forces near Russia's borders.
He emphasised that the US-led missile defence programme has become a "major destabilising factor inciting an arms race".
He pointed at a growing number of Nato intelligence flights near Russia's borders and an increasing pace of military drills, noting that they have "a clear anti-Russian character".
"The danger of provocations and military incidents has significantly increased," Mr Shoigu said.
Russia-West relations have sunk to their lowest level since the Cold War following Moscow's 2014 annexation of Crimea and support for separatists in eastern Ukraine, differences over the war in Syria and the allegations of Russian meddling in the 2016 US presidential election.
Mr Shoigu said Nato has stonewalled Moscow's attempts to engage in a dialogue, adding: "We aren't going to knock on the closed door, but will not leave attempts to apply pressure on us unattended."
He warned that Moscow will respond to Nato's moves by strengthening its defence capabilities to "ensure military security of Russia and its allies".
Tensions further escalated this month after the poisoning of an ex-Russian spy in Britain, leading to mass expulsions of diplomats by the West and Russia. Britain has blamed Moscow for the poisoning of former double agent Sergei Skripal and his daughter, accusations Russia has denied.
Sergei Naryshkin, the director of Russia's Foreign Intelligence Service, told the conference the attack on Mr Skripal was a "grotesque provocation rudely staged by the British and US intelligence agencies".
British and US officials have previously rejected similar Russian allegations.
"Washington has become fixated on fighting the non-existent Russian threat, and that fight has reached such a scale and acquired such absurd traits that we can talk about the return of the gloomy times of the Cold War," said Mr Naryshkin.
He said the US and its allies have been unable to adapt to global changes, including a growing role of China, Russia and other countries.
"The US and part of Europe have failed to prepare for such changes, they can't accept inevitable weakening of their once overwhelming clout," he said.
"Engulfed by fear of change, the West is ready to surround itself with a new Iron Curtain."