“We have not faced the prospect of Armageddon since Kennedy and the Cuban Missile Crisis,” the president said.

Biden, claiming to know Russian President Vladimir Putin “fairly well,” argued the leader is serious when he speaks about using “tactical nuclear weapons or biological or chemical weapons.” Resorting to these weapons shows his military is “significantly underperforming,” he added.

In an angry and fiery speech last week, Mr. Putin raised the specter of using nuclear weapons to hold on to his territorial gains, which Ukraine’s powerful counteroffensives have begun to erode. Mr. Putin said he would use “all available means” to defend Russian territory — which he has declared now includes four provinces of eastern Ukraine that Russia illegally annexed in recent days.

The atomic bombs the United States dropped on Japan in 1945, Mr. Putin said in that speech, had “created a precedent.”

His remarks and others by top Russian leaders represent the first time since 1962 that Moscow officials have made explicit nuclear threats.

Officials in Washington have been gaming out scenarios in which Mr. Putin might decide to use a tactical nuclear weapon to make up for the failings of Russian troops in Ukraine. In late February, Mr. Putin called for his nuclear forces to go on alert, but there has been no evidence that they did so. (NYT)

White House Press Secretary Karine Jean-Pierre said Tuesday the U.S. hasn’t seen a reason yet to adjust its nuclear posture as there’s been no sign that Russia is imminently planning to use nuclear weapons.

Critics ripped the president, arguing his policies helped get to this point.