"Russia today indisputably represents a far greater threat to our national security than Islamic extremist threats such as al-Qaeda and Isil[Daesh]," Carleton-Smith said in an interview with The Telegraph newspaper released late on Friday.
"Russia has embarked on a systematic effort to explore and exploit Western vulnerabilities, particularly in some of the non-traditional areas of cyber, space, undersea warfare… We cannot be complacent about the threat Russia poses or leave it uncontested. The most important conventional military response to Russia is the continued capabilities and coherence of the NATO alliance," Carleton-Smith argued.
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Russia has repeatedly said it did not plan to attack any NATO member. Moscow has suggested that the alleged Russian aggression was used as a pretext by the military alliance to boost its military build-up near the Russian border.