“This war is not merely about the black soil of the Donbas, nor the re-establishment of a Russian Empire, it’s about defeating our system and way of life politically, psychologically, and symbolically. How we respond as the pre-war generation will reverberate through history. Ukrainian bravery is buying time, for now.”

Downing Street insisted that a full military call-up was not on the table with a spokesman for Prime Minister Rishi Sunak saying the government had no intention of introducing conscription. He added that engaging in hypothetical wars was not helpful.

Sanders, an outspoken general who is liked within the army, is due to leave his post within six months. He recently criticised the shrinking of the British army by the middle of the decade, to its smallest since the Napoleonic era.

Documents recently leaked to the German newspaper Bild have revealed that Berlin is making contingency plans for a massive Russian assault on Western Europe, specifically the Baltic states.

Germany’s Defence Minister Boris Pistorius has made radical calls to prepare for war that would dramatically reorient its military after nearly eight decades spent in a multilateralist defensive mode.

He emphasised the urgent need for European Union countries to bolster their defence industries to prepare for potential challenges, especially in light of the possibility of reduced United States engagement on the Continent.

Two top Swedish officials have warned the country should brace for war as it prepares for the first stages of joining NATO. The country’s Civil Defence Minister Carl-Oskar Bohlin warned that action was needed rapidly to mitigate against a looming threat from Russia, pointing to the developing situation in Ukraine as evidence that war could spread to other parts of Europe.

Military chiefs in Estonia and Belgium are also among those urging their governments to prepare for a potential conflict with Moscow.

The chair of NATO’s military committee of national chiefs, Admiral Rob Bauer, said last week in Brussels the West should prepare for war with Russia in the next 20 years, and should “expect the unexpected”.

“We have to realise it’s not a given that we are in peace. And that’s why we [NATO forces] are preparing for a conflict with Russia,” he said.

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