President Vladimir Putin said on Tuesday that Russia will boost its nuclear arsenal by over 40 intercontinental missiles this year, in a move likely to further unnerve the West.
"This year the size of our nuclear forces will increase by over 40 new intercontinental ballistic missiles that will be able to overcome any, even the most technologically advanced, missile defence systems," Putin said at the opening of an exhibition of military hardware outside Moscow.
The declaration from Putin came as Russia reacted with fury to reports that the US is planning to bulk up its military deployments in Eastern Europe.
Tensions between Russia and the West are at their highest since the end of the Cold War over the conflict in Ukraine.
Kiev and its allies accuse Moscow of sending in troops and armour to back a separatist conflict in the east of the country but Russia has denied the claims.
The New York Times reported at the weekend that the Pentagon was poised to station heavy weapons for up to 5,000 American troops in several Eastern European and Baltic countries to deter Russian aggression.
The proposal, if approved, would be the first time since the end of the Cold War that the US has had heavy military equipment -- including battle tanks -- in newer NATO members that were once under Moscow's influence as part of the Soviet Union.
Poland said on Sunday it is in talks with the United States on the possibility of Washington storing heavy weaponry on its soil.
Russia's foreign ministry lashed out at the possible US deployment to the region, warning that the move by Washington could "take on a life of its own".
"The United States is fuelling tensions and nurturing its European allies' anti-Russian fears, also because it plans to use current tensions to expand its military presence and hence strengthen its influence in Europe," the ministry said in a statement Monday.