A top aide of Ukrainian President Volodymyr Zelensky said Ukraine's intelligence community believes the threat of Russian forces using nuclear weapons is "very high" following a string of embarrassing losses for Russian President Vladimir Putin.
In an op-ed published in The Atlantic on Friday, Andriy Yermak, head of the office of the the president of Ukraine, said Ukrainian officials do not think Russia's threats to use nuclear weapons are empty.
"Our intelligence agencies assess the threat of Russia's tactical nuclear-weapons use as 'very high.' And Russia's willingness to make nuclear threats presents a crisis not just for Ukraine, but for every country on Earth," Yermak wrote.
"The response to Russia's nuclear blackmail must be fierce and unequivocal, rejecting the very idea of making concessions to a nuclear aggressor," he continued.
Otherwise, Yermak warned, every dictatorial regime will scramble to attain nuclear weapons, and non-nuclear countries will do the same in self defense.
"Nonproliferation agreements will be worthless. Nuclear wars, with their millions of casualties, will follow," he said.
The warning from Yermak comes amid threats from Putin to use any means necessary to win the war in Ukraine. During a partial call-up of Russian reserves, Putin said, "When the territorial integrity of our country is threatened, we, of course, will use all the means at our disposal to protect Russia and our people."
"This is not a bluff. And those who try to blackmail us with nuclear weapons should know that the weathervane can turn and point towards them," he said.
His remarks raised concerns among the international community that the Russian military would use nuclear weapons.
Russian forces have suffered a string of losses in eastern Ukraine over the past month amid a major Ukrainian counteroffensive.
Most recently, the Russian military retreated from the city of Lyman, a major rail hub in the Donetsk region, after it was encircled by Ukrainian forces. On Friday, Putin announced the annexation of the area as well as three others, a move that's been widely viewed as illegal by the U.S. and its allies.
Yermak called on Ukraine's allies to take further steps to protect the country in the face of nuclear threats.
"A core group of Ukraine's allies, with significant military capabilities, would make a set of commitments that are both politically and legally binding. Alongside these commitments of military support, a broader group of international partners would offer a set of nonmilitary guarantees based on sanctions."
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