Russia ties most 'difficult' since Cold War: NATO

Speaking after US President Donald Trump said relations between Washington and Moscow had hit an all-time low, the alliance's chief said Russia's "destabilization" of eastern Ukraine had helped scupper hopes of a diplomatic reset.

"I think (it) is correct to say that NATO's relationship with Russia is more difficult than it has been any time since the end of the Cold War," Stoltenberg told CNN.

"At the end of the Cold War, we hoped to develop a close partnership with Russia.

"But especially after the illegal annexation of Crimea in 2014 and the continued Russian destabilization of eastern Ukraine, the relationship between NATO and Russia has deteriorated considerably."

Stoltenberg said that NATO was committed to avoiding a further spike in tensions and was pursuing a twin-track approach of "defense deterrence and dialogue."

"As long as we are strong, as long as we are predictable, we can also engage in political dialogue with Russia to try to avoid escalation and avoid a new Cold War," he said.