“Russia has demonstrated that it is prepared to use military force to secure and expand its national interest.”
Russia has come under scrutiny this year for allegations by the British government that it is behind the May poisoning of former Russian spy Sergei Skripal in the town of Salisbury. The U.K. says Russia used a highly toxic nerve agent called Novichok to carry out the attack, which left Skripal and his daughter critically ill.
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Skripal recovered, but a British woman died from coming in contact with the substance. Russia has denied any involvement in the poisoning.
“Russia has embarked on a systematic effort to explore and exploit Western vulnerabilities,” Carleton-Smith said. “Particularly in some of the non-traditional areas of cyberspace, undersea warfare.
“The Russians seek to exploit vulnerability and weakness whenever they detect it.”
Carleton-Smith led the U.K.’s military hunt for al-Qaida leader Osama bin Laden, and between 2012 and 2015 was head of the British Special Forces. He has spent the last two decades focused on fighting Islamic extremism.
He says the threat from ISIS has diminished due to military action from the U.S.-led coalition in Syria and Iraq.
WATCH ABOVE: Investigation underway after suspected Novichok poisoning victim in the UK dies
He went on to reinforce the importance of NATO in countering Russia.
“The most important conventional military response to Russia is the continued capabilities and coherence of the NATO alliance,” he said. “I would not support any initiative that diluted the military effectiveness of NATO.
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“We cannot be complacent about the threat Russia poses or leave it uncontested.”
U.S. President Donald Trump has consistently criticized the military alliance since his election, claiming the U.S. is paying too much into NATO and is being exploited by allies.
The Russian U.K. embassy responded by poking fun of Carleton-Smith’s comments on Twitter.