British Army MUST be ready for war within THREE years against 'axis of upheaval' of Russia, China, Iran and North Korea

He suggested Russia could seek “retribution” after its invasion of Ukraine, China could look to mount an assault against Taiwan and Iran and North Korea could continue to develop nuclear weapons.

Speaking on the sidelines of an annual army conference, Walker said: “The point here is when you think they [the Russians] are down, they will come roaring back to get their vengeance.”

He added: “That is why you get to this point by... 2027-2028 this convergence may have reached some sort of mutual singularity and your ability to deal with them in isolation - a specific crisis that can be managed by the rules based system - I think is significantly diminished.

"A problem in one area is likely to trigger a sympathetic detonation in another and therefore it is a global problem looked at from different perspectives around the world."

General Walker hopes to double the ability to the army by 2027, adding it will destroy an enemy force of at least three times their size by the end of the decade.

Despite not expressing too much concern about further costs, Walker cautioned against cuts to the British military.

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The Government last week launched a sweeping review of defence after eyebrows were raised about Sir Keir Starmer’s decision not to specify a timeframe for lifting defence spending to 2.5 per cent.

Concluding his remarks, General Walker said: "If we can double then triple our fighting power, any British land force will be able to destroy a force at least three times its size and keep on doing that.

"That way we will have every confidence in being ready and able to fight anyone and win."

However, an anonymous EU general recently warned about the drop in troops compared to Putin’s personnel.

They told The Times: “There is a concern about the British Army.

“We see they are facing difficulties regarding their human resources and also the equipment capabilities. The number of soldiers will be reducing in the next coming months.

“The main problem is the capability of the army to face a high intensity conflict. You must have mass, you must have numbers.

“In Ukraine, you can see we must have mass to fight the Russian army.”