‘Decisive’ action pledged if Russia uses nuclear arms

America and its allies will act “decisively” if Russia uses a tactical nuclear weapon in Ukraine, US national security adviser Jake Sullivan said on Sunday, reaffirming the White House’s previous response to mounting concerns that Vladimir Putin’s threats are in increased danger of being realised.

“We have communicated directly, privately and at very high levels to the Kremlin that any use of nuclear weapons will be met with catastrophic consequences for Russia, that the US and our allies will respond decisively, and we have been clear and specific about what that will entail,” Sullivan told CBS’s Face The Nation.

Sullivan said that the Russian leader Putin had been “waving around the nuclear card at various points through this conflict”, and it was a matter that Joe Biden’s administration has “to take deadly seriously because it is a matter of paramount seriousness – the possible use of nuclear weapons for the first time since the second world war”.