In a new interview with CNN, Biden offered a careful message to the Russian president about the disastrous consequences of using nuclear weapons.

When asked whether he thought that Putin, who has stated his preparedness to use every weapon in Russia’s arsenal, might actually consider using nuclear weapons, Biden responded, “I don’t think he will.”

“What I am talking about, I am talking to Putin. He, in fact, cannot continue with impunity to talk about the use of a tactical nuclear weapon as if that’s a rational thing to do,” Biden said. “The mistakes get made, the miscalculation could occur, no one could be sure what would happen and it could end in Armageddon,” he said, again stressing that a nuclear blast that kills thousands of people could lead to events spiralling out of control.

So far in the course of history, the only country to use a nuclear weapon is the US, detonating two atomic bombs on Hiroshima and Nagaski in 1945. The likelihood of Putin actually using nuclear weapons in combat has been frequently debated over the last few weeks, but the head of UK spy agency GCHQ said that they have not seen any indicators that Russia is preparing to use a tactical nuclear weapon despite Putin’s statements. UK spy chief Jeremy Fleming said that there were no signs that Russia was engaged in any technical preparatory steps. Many experts in Washington also estimate that there are many reasons why Putin would stop short of using nuclear weapons, such as the radioactive fallout in Russia or the fact that it may not actually be strategically smart.

Biden, however, felt the need to reiterate the dangers of possible escalation. CNN’s analysis argues that Biden is trying to create a “narrative of deterrence” around the situation. Given that Ukraine has no nuclear arsenal, it poses the question as to whether the US would mount a response if Putin were to take more drastic measures. CNN anchor Jake Tapper asked Biden to state the US red line for the US and NATO in Ukraine and what Washington would do if Putin bombed a nuclear plant in Ukraine or set off a tactical nuclear weapon.

The US President responded with “It would be irresponsible for me to talk about what we would or wouldn’t do.”

Meanwhile, NATO partners are set to discuss bolstering Ukraine’s air defence. More than 50 countries will gather on the sidelines of a NATO meeting in Brussels on Wednesday to discuss possible measures. This week, at least 26 people have been killed since Monday across Ukraine after Russia launched over 100 missile attacks. President Putin said the strikes were ordered as a retaliatory measure against Ukraine for the Crimean bridge explosion. Russia’s Federal Security Service has detained five Russian suspects and three citizens of Ukraine and Armenia in connection with the bombing of the bridge.

The upcoming gathering in Brussels is the first big NATO meeting since Russia’s increased escalation in Ukraine. NATO Secretary-General Jens Stoltenberg urged allies to send more air defence to Ukraine, stating the need for “short-range, long-range, air defence systems to take ballistic missiles, cruise missiles, drones, different systems for different tasks.”

NATO defence ministers will meet with partners from the Ukraine Defence Contact Group, an initiative established by the US to keep up arms supplies to Kyiv. They will then engage in a session on nuclear planning. Stoltenberg said that the alliance had not seen any changes in Russia’s nuclear posture, a similar observation made by that of GCHQ. But he affirmed the need to remain vigilant and monitor threats closely as the “veiled threats from Russia are dangerous and reckless.”

(Sources: Reuters, CNN)