Deputy Secretary General of NATO Alexander Vershbow said in Bucharest on Tuesday, Censor.NET reports.
"We face two very different but significant, long-term challenges - from Russia, and from terrorism and violent extremism - challenges that have re-shaped our view of our own security, and that will be with us for many years to come," he said.
"As long as Russia continues its aggression against Ukraine and attempts to intimidate NATO Allies and partners, we will do everything in our power to maintain a strong deterrence and defense," the official stressed.
Earlier, Financial Times reported that NATO is developing its own concept of responding to the threat of hybrid wars.
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