Russia is now regarded more as an enemy by NATO, according to the alliance’s senior official.

      “Clearly the Russians have declared NATO as an adversary, so we have to begin to view Russia no longer as a partner but as more of an adversary than a partner," Alexander Vershbow, the deputy secretary-general of NATO, told a group of journalists on Thursday.

      He insisted that the current Ukraine crisis fundamentally changed the NATO-Russia relationship.

      "In central Europe, clearly we have two different visions of what European security should be like… We still would defend the sovereignty and freedom of choice of Russia's neighbors, and Russia clearly is trying to re-impose hegemony and limit their sovereignty under the guise of a defense of the Russian world," he was quoted by Fox News as saying.

      In April, NATO suspended all "practical civilian and military cooperation" with Russia, following a raft of sanctions imposed by the US and the EU. The US also put space and military cooperation on hold, followed by some of its NATO allies, including the UK.