Former national security adviser H.R. McMaster on Sunday cautioned Russian President Vladimir Putin against carrying out his threat of a nuclear attack, saying it would be a "suicide weapon" for him.
McMaster, a retired U.S. Army lieutenant general who served as a national security adviser under former President Trump, also told CBS's Margaret Brennan on "Face the Nation" that despite Putin's threats, the western world does not have to respond with the same escalation.
"I think the message to [Putin] is if you use a nuclear weapon, it's a suicide weapon," McMaster said, adding that "the response from NATO and the United States doesn't have to be nuclear."
Last month, following a successful Ukrainian counterattack that pushed Russian troops back in the eastern region of Ukraine, Putin warned of nuclear attacks and said it was "not a bluff."
The Biden administration has been warning the Kremlin against any nuclear attacks, Secretary of State Antony Blinken said last month, and has privately told Russian officials to "stop the loose talk" on the potential use of a nuclear weapon.
McMaster said on Sunday that Putin is under "extreme pressure" amid the war in Ukraine and a partial mobilization order issued last month to draw up some 300,000 reservists in Russia. The mobilization order drew widespread protests and forced thousands of Russians to flee the country.
"What we might be at here is really at the precipice of really the collapse of the Russian army in Ukraine, a moral collapse," McMaster said. "They must really be at a breaking point. If you look at just the numbers of casualties, the vast area that they're trying to defend, and now, of course, Russia is trying to mobilize conscripts and send them to the front untrained."
The former national security adviser estimated that Putin's nuclear threat is the "only quiver he has left" as the Russian leader struggles in the war.
"We ought to take it seriously," McMaster said of the nuclear threats. "We have to, but we ought to not allow this to cow us in terms of the support for the Ukrainians."
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