Biden warns world would face ‘Armageddon’ if Putin uses a tactical nuclear weapon in Ukraine

In his starkest assessment yet, US president says world is the closest it has come to nuclear catastrophe in sixty years

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Joe Biden has warned the world could face Armageddon" if Vladimir Putin uses a tactical nuclear weapon to try to win the war in Ukraine.

The US president made his most outspoken remarks to date about the threat of nuclear war, at a Democratic fundraiser in New York, saying it was the closest the world had come to nuclear catastrophe for sixty years.