'A serious mistake': US warns Moscow against using nukes as Russia accuses Ukraine of dirty bomb plot

President Joe Biden on Tuesday issued another warning to Russian President Vladimir Putin about the severe consequences that Russia would face if nuclear weapons are used in the ongoing invasion and occupation of Ukraine.

“I spent a lot of time today talking about that,” Biden said in response to a question at a press conference. “Let me just say Russia would be making an incredibly serious mistake if it were to use a tactical nuclear weapon."

His remarks come as Russia's United Nations delegation submitted a draft resolution to the Security Council – of which Russia is a member – requesting an investigation into its allegations that Ukraine is planning to launch a dirty bomb attack that it can blame on Russia.

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"We're quite satisfied because we raised the awareness," Russia's Deputy UN Ambassador Dmitry Polyanskiy told reporters, per Reuters. "I don't mind people saying that Russia is crying wolf if this doesn't happen because this is a terrible, terrible disaster that threatens potentially the whole of the Earth."

The accusations have been dismissed by the West as propaganda and possibly an attempt by Russia to run cover for future war crimes.

"I’m not guaranteeing that it’s a false flag operation yet. We don’t know. It would be a serious, serious mistake," Biden said.

Representatives from Paris, Washington, and London preceded that point on that in a joint statement on Monday, declaring that "our countries made clear that we all reject Russia’s transparently false allegations that Ukraine is preparing to use a dirty bomb on its own territory. The world would see through any attempt to use this allegation as a pretext for escalation. We further reject any pretext for escalation by Russia."

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British Deputy UN Ambassador James Kariuki noted that "we've seen and heard no new evidence" and that "this is pure Russian misinformation of the kind of we've seen many times before and it should stop."

Ukrainian Foreign Minister Dmytro Kuleba, meanwhile, has welcomed inspections by the UN's nuclear watchdog at two undisclosed sites.

Putin has repeatedly threatened to tap into his atomic arsenal to blackmail the United States and the North Atlantic Treaty Organization from increasing military aid to Ukraine since the February 24th inception of his "special military operation." Russia's nuclear doctrine states that Moscow reserves the right to use nuclear weapons to defend Russian territory – which it now illegally claims includes the Western Ukrainian regions of Luhansk, Donetsk, Zaporizhzhia, and Kherson – where the Kremlin held sham referenda to join Russia earlier this month. Russia's doctrine also permits nuclear first strikes if Putin perceives an immediate existential threat to the survival of the state. But intelligence reports indicate that Putin has not made any moves toward nuclear escalation.

Nonetheless, Biden is maintaining his red line.

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