President Vladimir Putin on Tuesday pledged Russia would build weapons that could pierce any anti-missile shield as he accused the United States and its allies of looking to shackle Moscow's nuclear capabilities.
"As we have repeatedly said, we will focus... on offensive systems capable of overcoming any anti-missile defence systems," Putin said at a government meeting on the defence industry in the Black Sea city of Sochi.
Russia has been locked in a feud for years over NATO plans to build a missile-defence system in Europe that it says is aimed against Iran but Moscow says is really directed at Russia.
"References to the Iranian and North Korean nuclear missile threats are a cover-up," Putin said.
The "true intentions" of the missile shield were aimed "at neutralising the strategic nuclear potential" of Russia, he said.
In May, NATO condemned Russia's plans to deploy nuclear-capable missiles in Kaliningrad, a Russian region sandwiched between Lithuania and Poland, as well as its increased number of nuclear bomber flights.
Russia's relations with the West reached their post-Cold War nadir over the Ukrainian crisis.