Intelligence community leaders said Tuesday during a House Intelligence Committee hearing that Russian President Vladimir Putin’s veiled nuclear threat should be taken seriously.

Ranking Member Mike Turner (R-OH) asked top intelligence officials testifying whether Russian President Vladimir Putin would be willing to use nuclear weapons if the U.S. or NATO intervened in the Ukraine war to protect innocent civilians.

Central Intelligence Agency Director Williams Burns responded:

In response to your direct question about a scenario in which NATO and the United States were directly involved in military conflict with Russia, you know, Russian doctrine holds that you escalate to deescalate, so I think the risk would rise according to that doctrine of, in extremis, you know, the Russian leadership considering the use of tactical nuclear weapons, but I stress that that’s only in that specific circumstance that you describe of a direct military conflict between NATO and Russia.

Defense Intelligence Agency Army Lt. Gen. Scott Berrier warned that Putin should be taken at his word.

“I also believe that when he says something we should listen very, very carefully and maybe take him at his word,” he said, adding, “This question is the one that analysts are pondering right now and I think we really need to do some more work on it.”

Director of National Intelligence Avril Haines said she thought Putin was “signaling” in order to deter the U.S. or NATO from intervening, but said, “We obviously take it very seriously when he’s signaling in this way…but we do assess that he’s effectively signaling that he’s attempting to deter.”

Putin has warned other countries not to intervene in the war, threatening “consequences that you have never experienced in your history,” and on February 27, put Russian nuclear forces on “special combat readiness.”

Haines said that was not a technical term that relates to a specific alert status, but said the move was “unusual.”

“We’re watching very closely for movements — anything related to his strategic nuclear forces — and we’re not seeing something at this stage that indicates that he is doing something different than what we’ve seen in the past,” she added.

Their remarks come as some lawmakers in Congress are calling for the Biden administration to consider enforcing a no-fly zone over Ukraine, which would entail direct U.S. military involvement and necessitate shooting down Russian planes over Ukraine.

So far, the Biden administration has said no U.S. forces would fight in Ukraine and have said it is not considering enforcing a no-fly zone, but calls for involvement will likely continue as the war drags on and more Ukrainian civilians are killed.

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