Russia's deployment of its S-400 air missile defense system and ballistic Iskander missile in the Russian enclave of Kaliningrad "is destabilizing to European security," the U.S. State Department said on Monday in response to reports citing the head of the defense committee in Russia's upper house of parliament.
"Russia has made threats to move its Iskander missiles to Kaliningrad for the past decade in response to a variety of developments in Europe, none of which demand such a military response," State Department spokesman John Kirby told reporters.
"We call on Russia to refrain from words or deeds that are inconsistent with the goal of promoting security and stability," he added.
Moscow will deploy S-400 surface-to-air missiles and nuclear-capable Iskander systems in the exclave of Kaliningrad in retaliation for NATO deployments, a senior pro-Kremlin lawmaker was quoted as saying on Monday.
Russia has previously said it periodically sends Iskanders to Kaliningrad, but until now it has said these were routine drills. Moscow has not linked the moves explicitly with what it says is a NATO military build-up on Russia's western borders. Kaliningrad is a Russian province between Poland and Lithuania.
After the election as U.S. president of Donald Trump, who has said he wants closer ties with the Kremlin and has , some analysts predict an emboldened Moscow could become more assertive in eastern Europe.
Viktor Ozerov, chairman of the defense committee in the Federation Council, Russia's upper house of parliament, said in remarks reported by RIA news agency that Russia was forced to react to the planned U.S. missile shield in eastern Europe.
"As response measures to such threats we will have... to deploy additional forces... This reinforcement includes deployment of S-400 and Iskander systems in Kaliningrad," the agency quoted Ozerov as saying.
The defense ministry did not immediately respond to a Reuters request for comment on Ozerov's remarks.
Also on Monday, Russian President Vladimir Putin was quoted talking about how Russia has to respond to what it perceives as a threat from U.S.-led forces in eastern Europe.
"Why are we reacting to NATO expansion so emotionally? We are concerned by NATO's decision making," RIA quoted him as saying in an interview for a documentary that will be broadcast by Russian TV later on Monday.
"What should we do? We have, therefore, to take countermeasures, which means to target with our missile systems the facilities, that, in our opinion, start posing a threat to us," Putin said.