US says it told the Kremlin that Russia will face 'catastrophic consequences' if it uses tactical nuclear weapons in Ukraine

A top Biden administration official said that the White House warned Russia that it would face "catastrophic consequences" if it moved to use nuclear weapons.

Jake Sullivan, the White House national security adviser, told CBS' 'Face The Nation' on Sunday that any use of nuclear weapons would be met with catastrophic consequences for Russia.

Sullivan said that the US and its allies would respond "decisively." If Russia uses nuclear weapons, the United States will respond in kind, as a matter of principle.

He said that despite Putin waving the "nuclear card" at various points throughout the war, the Biden administration is taking his threats seriously.

Russia has the largest nuclear arsenal in the world with strategic nuclear weapons for use against targets like bases and cities and tactical nuclear weapons for battlefield use. Russia is able to conduct nuclear strikes from land, air, and sea.

Nuclear weapons have not been used in Japan since the US dropped atomic bombs on the city of Nagasaki in World War II.

Sullivan's comments come after Putin delivered a rare televised address last week announcing partial military deployment and threatening to use nuclear weapons. The Russian leader baselessly accused Western countries of "nuclear blackmail" and said that they are trying to provoke the Kremlin with their own nuclear weapons stockpiles.

"If you allow yourself to make such statements about Russia, I would like to remind you that our country also has various means of destruction, and for some components more modern than those of the NATO countries," Putin stated.

If the territorial integrity of our country is threatened, we will use all the means at our disposal to protect Russia and our people.

Western officials have warned that Putin could use a nuclear weapon if he felt backed into a corner.

"We can't take lightly the threat posed by a potential resort to tactical nuclear weapons or low-yield nuclear weapons, given the setbacks that they've faced so far," William Burns said in April.

The Russian military is struggling in the face of a Ukrainian counteroffensive. Kevin Ryan, a former defense attache to Russia, told Insider in September that he's more concerned about Putin using a nuclear weapon.

Other Russia watchers don't think that Putin would use mass destruction.

Ivo Daalder told Insider last Wednesday that anyone who finds it necessary to say that he's not bluffing most likely is.

The retired admiral told MSNBC on Friday that he's not losing sleep over Putin's nuclear threats. He doesn't think Putin will use a nuke.