Russian President Vladimir Putin on Tuesday blamed the West for escalating tensions in Europe, saying it had incorrectly assessed the outcome of the Cold War.

Speaking to senior military officials, Putin said Russia would respond “adequately” to any Western aggression and would develop its army further.

Russia has amassed tens of thousands of troops on the border with Ukraine, demanding that NATO refuse to accept the former Soviet republic as a member and guarantee that no weapons or troops will be deployed there.

Speaking at the same meeting, Russian Defence Minister Sergei Shoigu said the United States had deployed some 8,000 troops near Russian borders and, alongside NATO allies, frequently performed flights by strategic bomber planes close to Russia.

Attempts by NATO to get the Ukrainian army involved in the alliance’s activities present a security threat, Shoigu said.

Earlier on Tuesday, a senior Russian diplomat said contacts had already begun between Moscow and Washington on the issue of security guarantees that Russia is seeking, and there was a possibility that the sides would reach an understanding.