There is no doubt that Russia has threatened nuclear attack, now.
www.politico.eu
And Medvedev currently views the captured Ukrainian territories as "Russian lands."
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Nuclear weapons on the table if Ukraine counteroffensive succeeds: Russia’s Medvedev
There would be ‘no other way out’ if Kyiv takes Russian territory, says the former Russian president and current National Security Council deputy chairman.
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“There would simply be no other way out” of using nuclear weapons if the Ukrainian offensive succeeded in taking Russian territory, Medvedev, former Russian president and current National Security Council deputy chairman, said in a post on social media.
“Just imagine that the NATO-supported ukrobanderovtsy’s offensive turned out successful, and they took away a part of our land: Then we would have to, following the president’s degree of 02.06.2020, use the nuclear weapon,” Medvedev wrote, referring to followers of Stepan Bandera, a nationalist leader who waged a violent campaign for Ukrainian independence in the 1930s and 1940s.
And Medvedev currently views the captured Ukrainian territories as "Russian lands."