Zelenskyy says the world must 'be ready' for Russia to attack Ukraine with tactical nukes

• Zelenskyy said the world must be prepared for the possibility of Russia attacking Ukraine with tactical nuclear weapons.
• Tactical nukes are designed for use on a battlefield or for a limited strike. Russia is estimated to have 2,000 of them.

Ukrainian President Volodymyr Zelenskyy said the world must be prepared for the possibility of Russia attacking Ukraine with tactical nuclear weapons.

In an interview with CNN's Jake Tapper published on Friday in Kyiv, Zelenskyy said Russian President Vladimir Putin could use either nuclear or chemical weapons at some point during the war in Ukraine.

"We should think — not be afraid, not be afraid — but be ready," Zelenskyy said. "But that is not a question for Ukraine, not only for Ukraine but for all the world, I think."

Zelenskyy said Ukrainian lives don't matter to Putin, which could prompt him to launch such an attack in a war where his forces have failed to take any major cities at a cost of an estimated 10,000 Russian soldiers' lives.

Just days after Russia's February 24 invasion of Ukraine, Putin ordered Russia's nuclear deterrent forces on high alert, blaming NATO and Western sanctions. The move prompted immediate backlash from the international community.

Last month, Kremlin spokesperson Dmitry Peskov said Russia would use nuclear weapons only if it felt as though its existence was threatened by the West.

In response, NATO Secretary General Jens Stoltenberg called out Russia for "nuclear saber-rattling," and slammed Moscow for "contradicting" its past statement about wanting to avoid nuclear conflict.

Tactical nuclear weapons, also known as battlefield nukes, are designed to be used on a smaller scale, on the battlefield or for a limited strike. Since the Cold War, both Russia and the United States have decreased their nuclear arsenal, but it's estimated that Russia still has 2,000 tactical nukes, while the U.S. has around 200.

Researchers from Princeton's Science and Global estimate that if Russia were to use tactical nukes, more than 91 million people in Russia, the US, and NATO-allied countries could be killed within three hours. The researchers created a simulation showing how even one "nuclear warning shot" from Russia could quickly escalate into nuclear war.

"This project is motivated by the need to highlight the potentially catastrophic consequences of current US and Russian nuclear war plans. The risk of nuclear war has increased dramatically in the past two years," the project states on its website.

Although the chances of Putin using a nuclear weapon are slim, some experts believe he could use one if he became desperate enough.

"It's not a good thing, and it's not something I think everybody wants to jump to — including Putin. But this is everything for him now," Retired Brig. Gen. Kevin Ryan, a former defense attaché to Russia and senior fellow at Harvard's Belfer Center for Science and International Affairs, said of the war with Ukraine. "If he doesn't accomplish this, his own people will take him out."