Former clandestine CIA officer Will Hurd called for Joe Biden to further escalate sanctions on Vladimir Putin's Russia — and warn the Kremlin that NATO will mess them up if the conflict expands.

Hurd, who also served South Texas as a Republican congressman, was interviewed on CNN on Monday.

"As you see that Putin put his nuclear deterrence forces on essentially alert — this is a step up, one step closer to being able to use nukes — are you concerned that he will?" CNN's Brianna Keilar asked.

"We need to be prepared for him to use those nuclear weapons," said the former congressman, who served on the House Permanent Select Committee on Intelligence.

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"I think looking at this as just a threat would be the wrong move," he explained. "I think this is an opportunity to escalate further sanctions. Let's stop nickel and diming — and every financial sanction we have available, let's put it now because this is an actual threat."

"We have this U.N. vote that's going to be coming up. I think President Biden should go to New York and implore the entire U.N. to support establishing a no-fly zone over Ukraine," Hurd said. "I think President Biden should fly to Poland, get [French President Emmanuel Macron] to show up, and the new chancellor from Germany to show up and say, 'If you step one foot, one Russian boot comes into NATO countries, we will be prepared to defend and we will mess you up.'"