Russia is to add more than 40 intercontinental ballistic missiles to its nuclear arsenal in 2015, President Vladimir Putin has announced.
"More than 40 new intercontinental ballistic missiles able to overcome even the most technically advanced anti-missile defence systems will be added to the make-up of the nuclear arsenal this year," said Putin in a speech at an arms fair outside Moscow.
The announcement comes after Russian officials denounced US plans to station heavy military equipment in central Europe, with relations between Russia and the West having risen to their lowest point since the Cold War in the wake of the Ukraine crisis.
Russia has warned that it will respond if the US carries through plans announced on 15 June to station equipment, including tanks and infantry fighting vehicles, in Nato states in eastern Europe that were formerly part of the Soviet Union.
"The feeling is that our colleagues from Nato countries are pushing us into an arms race," RIA news agency quoted Deputy Defence Minister Anatoly Antonov as saying on the sidelines of the arms fair.
Moscow has begun a modernisation of its nuclear arsenal, with new ballistic missiles being deployed and modern bombers and submarines developed.
Over recent years, a number of obsolete nuclear weapons have been withdrawn from Russia's arsenal, meaning the country's number of nuclear weapons has decreased.
Russian state media and officials have stepped up anti-western rhetoric in the wake of the Ukraine crisis, with Russia Today chief Dmitry Kiselyov saying last year that Russia could reduce the US to "radioactive dust", and the Russian ambassador to Denmark warning that Russia would target its warships if Copenhagen decided to join the Nato's missiles air defence shield.