Russia accused NATO on Wednesday of encroaching on its borders and seeking to change the strategic balance of power, forcing Moscow to take steps to protect its interests and security.
The comments by Kremlin spokesman Dmitry Peskov came a day after Russia and the West accused one another of endangering global security, adding to tensions over the conflict in Ukraine, in which pro-Russian separatists have seized land in the east after Moscow annexed Crimea from Kiev in early 2014.
"It's not Russia that's approaching someone's borders. It's NATO's military infrastructure that is approaching the borders of Russia," Peskov told reporters.
"All this … forces Russia to take measures to safeguard its own interests, its own security."
Peskov said the West had increasingly resorted to "unconstructive and confrontational" Cold War-style rhetoric and that Russia had never wanted strife.
President Vladimir Putin said Tuesday that Russia would add more than 40 new intercontinental ballistic missiles to its nuclear arsenal this year, prompting NATO's chief to accuse Moscow of dangerous "saber rattling."
A day earlier, Russian officials had denounced a U.S. plan to station tanks and heavy weapons in NATO member states on Russia's border as the most aggressive act by Washington since the Cold War.
Putin's top foreign policy adviser also said on Wednesday that Russia would not be dragged into an arms race with the West as this would hurt the economy.
"Russia is not entering an arms race. Russia is trying to react in some ways to certain threats but nothing more than that. We are not entering any arms race because that would hurt our capabilities in the economic sphere," Yury Ushakov said.
Briefing reporters on an economic forum later this week in St. Petersburg, Ushakov said Putin would meet Greece's prime minister on Friday to discuss the planned Turkish Stream gas pipeline and other issues.
Ushakov said Putin would also meet the Saudi defense minister to discuss bilateral cooperation, including on energy, as well as the head of the International Atomic Energy Agency, with whom he would discuss Iran's nuclear program. Putin will also meet the chief executive of Royal Dutch Shell, he said.
