Russian invaders (Photo: resources of the occupiers)

Russia may need five years to fully capture the Donetsk, Luhansk, Kherson, and Zaporizhzhia oblasts, General Roly Walker, Chief of the General Staff of the British Army, said at a conference at the Royal United Services Institute in London, as quoted by Sky News.

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If Russia continues its aggression against Ukraine at the same pace, it will likely take five years to "grind their way" to the minimum goal of full occupation of just four regions, with a loss of 1.5 to 1.8 million soldiers killed and wounded, Walker said.

Russia would also have to spend billions of pounds worth of military equipment to fully capture the partially occupied Ukrainian regions.

Walker warned that Russian dictator Vladimir Putin must be defeated in Ukraine, or he will target NATO countries.

"It [Russia] has just started in Ukraine, so it must fail in Ukraine otherwise where does it go next?" he said.

At the same time, the general noted that in a war of attrition, "there are no winners."

"It is an utter devastation for both sides and lost generations," he stressed.

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