Ukrainian President Volodymyr Zelenskyy on Sunday warned that nuclear war "could be a reality."

"[Russian President Vladimir Putin] wants to scare the whole world," Zelenskyy said during an interview on CBS' "Face The Nation."

"Look, maybe yesterday it was bluff," Zelenskyy added. "Now, it could be a reality.

"He targeted and occupied our nuclear power plant and the city of Enerhodar. This nuclear station has six blocks. And ... he continues his blackmail related to us exporting electricity to Europe.

"I don't think he's bluffing," the Ukrainian president continued. "I think the world is deterring it and containing this threat. We need to keep putting pressure on him and not allow him to continue."

Zelenskyy's comments come after he pledged to treat surrendering Russian troops in a "civilized manner."

"You will be treated in a civilized manner ... no one will know the circumstances of your surrender," the Ukrainian leader stated in Russian during a late address to the nation Saturday.

Conversely, Zelenskyy's call for civility follows Putin's signing of a bill that passed the Russian parliament last week. The bill would punish any soldier who deserts, voluntarily surrenders or disobeys an order to fight with 10 years in prison.

Putin threatened to use "all the means at our disposal" to protect Russia in its war against Ukraine during an announcement where he called 300,000 reservists up to fight.

During an interview with Piers Morgan, clinical psychologist Jordan Peterson called it "naïve" to think Russia would lose to Ukraine.

"Or that we're going to win.

"I don't understand that. What do you mean we're going to win? What are we going to win here exactly?" Peterson asked Morgan.

The professor qualified that even if Putin retreated, Ukraine would be left in "smoking ruins."

• Zelenskyy Demands 'Global Control' Over Russia's Nuclear Capabilities
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