British citizens should be "trained and equipped" to fight in a potential war with Russia - as Moscow plans on "defeating our system and way of life", the head of the British Army has said, Sky News reported.
General Sir Patrick Sanders, the outgoing Chief of the General Staff (CGS), said increasing army numbers in preparation for a potential conflict would need to be a "whole-of-nation undertaking".
The comments, first reported by the Daily Telegraph, are being read as a warning that British men and women should be ready for a call-up to the armed forces if NATO goes to war with Vladimir Putin.
It comes after Defense Secretary Grant Shapps said in a speech last week that we are "moving from a post-war to pre-war world" and the UK must ensure its "entire defense ecosystem is ready" to defend its homeland.
But Downing Street ruled out any move towards a conscription model, saying that army service would remain voluntary.
Sanders has been a vocal critic of cuts to troop numbers and military spending, according to Sky News.
In his speech at the International Armoured Vehicles conference in west London, he said the UK must urgently expand the size of the army to around 120,000 within three years - up from around 74,000 now.
But he said "this is not enough" and training and equipping a "citizen army" must follow.
He pointed to this happening across Europe, telling the audience: "Our friends in eastern and northern Europe, who feel the proximity of the Russian threat more acutely, are already acting prudently, laying the foundations for national mobilization.
"As the chairman of the NATO military committee warned just last week, and as the Swedish government has done...taking preparatory steps to enable placing our societies on a war footing when needed are now not merely desirable but essential."
Sanders added: "We will not be immune and as the pre-war generation we must similarly prepare - and that is a whole-of-nation undertaking.
"Ukraine brutally illustrates that regular armies start wars; citizen armies win them."