Russian President Vladimir Putin said on Friday he has ordered the military to prepare a "symmetric response" after Washington tested a formerly banned missile.
Putin said he had ordered an analysis of "the level of threat for our country created by the actions of the US and to take comprehensive measures to prepare a symmetric response".
The US Department of Defense said Monday it had tested a type of ground-launched missile that was banned under the 1987 INF agreement, which limited the use of nuclear and conventional medium-range weapons.
Moscow and Washington ripped up the pact early this month after several months of accusing one another of breaching its conditions.
Speaking at a government meeting, Putin said Sunday's launch of the nuclear-capable Tomahawk missile with a MK-41 launcher confirmed prior suspicions that the United States had planned to place banned weapons in Europe.
He said Moscow was against placement of the launchers in Poland in Romania, but the US denied they could be used to launch Tomahawks.
"Now the fact of the violation is clear, and it's useless to deny it," Putin said. "The question is, how do we know what will be placed in Romania and Poland?"
Russia "will not be pulled into an expensive arms race destructive for our economy" but will need to "ensure the safety of our people and our country". he said.
Washington had denied the test marks the start of an arms race as it denied having plans to develop nuclear-tipped weapons.