The United States' decision to store heavy weapons in the Baltic states and several Eastern European countries in an attempt to ease their fears stemming from Russia's intervention in Ukraine and annexation of Crimea has invited a strong reaction from Moscow. Calling the U.S. move "the most aggressive step by the Pentagon and NATO" since the Cold War, a senior Russian Defense Ministry official, Gen. Yuri Yakubov, said in mid-June that Russia would have no other choice but to upgrade its forces on its western border by adding troops, tanks, artillery, airplanes and missiles there. President Vladimir Putin stated that Russia would add over 40 nuclear intercontinental ballistic missiles capable of overcoming any missile defense system. The two sides must take concrete steps to restore trust and end this escalating situation that threatens to revive the Cold War.

Tensions between the U.S. and Russia heightened after a June 13 New York Times report quoted U.S. and allied officials as saying that the Pentagon planned to "store battle tanks, infantry fighting vehicles and other heavy weapons for as many as 5,000 American troops in several Baltic states and Eastern European countries." Russia reacted quickly. Yakubov made the statement two days later, followed by Putin, who, speaking at the opening of a weapons show held near Moscow, announced the plan to beef up Russia's nuclear arsenal with more than 40 new ICBMs — a move that would doom U.S.-Russia cooperation to reduce their nuclear arsenals. Like Yakubov, he characterized the U.S. move as the most aggressive act since the Cold War and said that Russia "will be forced to aim our armed forces ... at those territories from where the threat comes." Expressing concern, U.S. Secretary of State John Kerry said that no one wants stepping backward "to a kind of a Cold War status."

The formal announcement by the U.S. government of its plan to pre-position heavy weapons on some of its European allies' territories for use by an armored brigade came on June 23 when Defense Secretary Ashton Carter said in the Estonian capital of Tallinn that "Estonia as well as Lithuania, Latvia, Bulgaria, Romania and Poland have agreed to host company to battalion-sized elements of this equipment." Although Carter said the equipment is for training and exercises, and the U.S. decision falls short of permanently stationing troops, it represents the first time that the U.S. will store heavy weapons in the new NATO member states that were either part of the Soviet Union — the three Baltic states — or belonged the Soviet bloc during the Cold War.