US President Joe Biden raised alarm Thursday that the world is on the precipice of a nuclear catastrophe for the first time since the Cold War.

“We have not faced the prospect of Armageddon since (President John F.) Kennedy and the Cuban missile crisis,” the president said at a Democratic fundraiser.

“I don't think there's any such thing as the ability to easily (use) a tactical nuclear weapon and not end up with Armageddon,” he added.

The comments come after Russian President Vladimir Putin raised the specter of nuclear confrontation last month as he prepared to annex more Ukrainian territory. Putin and his proxies ultimately completed the annexation process this week following referendums denounced by the West as a fraudulent “land grab.”

Biden said he knows Putin “fairly well,” adding he is “not joking when he talks about the potential use of tactical nuclear weapons or biological or chemical weapons, because his military is, you might say, significantly underperforming.”

Ukrainian forces have been making strident advances in territories formerly occupied by Russia, routing them in the northern Kharkiv region and pressing towards a major advance on Kherson in the south.