Responding to NATO’s announcement of a “Readiness Action Plan,” a top Kremlin official has said that Russia will review its military strategy “to reflect new security threats,” state news agency RIA Novosti reported Tuesday.

“I have no doubts that the issue of NATO military infrastructure encroaching on our borders, including through the expansion of the alliance, will remain among the biggest military threats to the Russian Federation,” Mikhail Popov, deputy secretary of Russia’s National Security Council, told RIA Novosti.

On Monday, NATO Secretary General Anders Fogh Rasmussen had announced plans for formation of a “very high readiness force…to deploy at a short notice” ahead of a NATO summit in Wales. This force, he said, was needed to respond to Russian aggression in Ukraine, and “could include several thousand troops.”

The two-day summit, which is scheduled to begin Thursday, will also be attended by U.S. President Barack Obama. The start of the summit will coincide with a self-imposed deadline from the European Union to announce further economic sanctions against Russia.

Popov reportedly said that the West was “aggravating tensions with Russia” and that NATO’s actions would be a key factor in determining Moscow’s future military strategy, although he did not give out details.

Popov's statements come just a day after Ukrainian defense minister Valeriy Heletey warned of a “great war” with Russia, “the likes of which Europe has not seen since the Second World War.”

The conflict in eastern Ukraine, which began in mid-April when Ukraine's government sent troops to put down an uprising by pro-Russian separatists in the Donetsk and Luhansk regions, has so far killed over 2,200 people and left over 3,200 injured.