Sir Jeremy Fleming, head of intelligence agency GCHQ, has revealed whether the UK would know if Russia was planning a nuclear strike.
Vladimir Putin has made a number of threats over recent weeks, as well as continuing to cause devastation across Ukraine, as the war shows no sign of slowing down.
"I would hope that we will see indicators if they started to go down that path", he told BBC Radio 4. "Any talk of nuclear weapons is dangerous, we need to be very careful how we're talking about that."
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