The Kremlin said on Tuesday that the four regions of Ukraine that Moscow declared it had annexed in recent weeks fall under the protection of Russia's nuclear arsenal.
Asked by reporters if the regions were under Moscow's nuclear umbrella, Kremlin spokesman Dmitry Peskov said: "All these territories are inalienable parts of the Russian Federation and they are all protected. Their security is provided for at the same level as the rest of Russia's territory."
Russian President Vladimir Putin said last month that Moscow was ready to use nuclear weapons if necessary to defend the "territorial integrity" of Russia.
US President Joe Biden said on Oct. 6 that his threat had brought the world closer to "Armageddon" than any time since the 1962 Cuban Missile Crisis when many feared a nuclear war might be imminent.
Putin last month proclaimed that the territories Moscow was taking from Ukraine would be part of Russia "forever." But Russia does not wholly control any of the four regions and has yet to define its borders.
Annexation is illegal - Ukraine
The annexation was condemned as illegal by Ukraine, its Western allies and an overwhelming majority of countries in the United Nations General Assembly.