Secret discussions are under way between western allies over how to arm what they expect to be fierce Ukrainian resistance in the event of a Russian invasion that topples the Kyiv government.

Boris Johnson laid bare the case for such a move in a dramatic speech to the Munich security conference where he stated it was in the collective self-interests of the west for any Russian invasion to “fail and be seen to fail”…

He said: “A lightning war would be followed by a long and hideous period of reprisals and revenge and insurgency, and Russian parents would mourn the loss of young Russian soldiers, who in their way are every bit as innocent as the Ukrainians now bracing themselves for attack.

“If Ukraine is overrun by brute force, I fail to see how a country encompassing nearly a quarter of a million square miles – the biggest nation in Europe apart from Russia itself – could then be held down and subjugated for ever.”