Defence chiefs have drawn up plans to cut 20,000 troops from the military and reduce the size of the Royal Marines, replacing the MoD’s firepower with cyber warfare and space technology.
Mandarins have suggested the scrapping of RAF air bases and a fleet of Hercules planes and Puma helicopters in a bid to save money, The Sunday Times reported.
The Treasury has asked departments to make savings of 5 per cent or more as part of a wider review of Government spending, while Boris Johnson has appointed a history professor to personally oversee any cuts to UK defence capability.
Draft plans suggest a significant chunk of the Royal Marines’ capability could be axed, including its artillery, engineers and landing craft.
Money would instead be invested in new cyber and space warfare technology.
Downing Street said it did not recognise the plans when they emerged on Sunday and the Ministry of Defence said it would not comment on the detail of the leak, but pointed to a Government commitment to increase defence spending each year above the rate of inflation.
“The MoD is progressing its contribution to the Integrated Review by planning how best to meet tomorrow’s threats within that increasing budget,” a spokeswoman said.
The Government has also promised NATO that it will continue to spend more than 2 per cent of GDP on defence.
But both spending pledges are pegged to national economic output, which has fallen dramatically during the coronavirus crisis.
Defence bosses will therefore be able to shrink the budget in real terms without breaking a manifesto pledge.
The leaked plans are understood to be a draft, and no final decisions have yet been taken.
Lord West of Spithead, a former First Sea Lord and security advisor to Downing Street, suggested that the plans could have been drawn up to gauge Westminster’s reaction to dramatic changes to the UK’s armed forces.
“I imagine that all sorts of things are being talked about,” he said.
“They’ll be floating them, and quite often, let’s face it, people have floated ideas to see what the reaction is from members of parliament, peers, the media and everything.
“That could be what is going on.”
Lord West also suggested replacing hard defence capability with space, cyber and robotic technology could only go so far to aid the UK in fighting conventional wars.
“The Treasury always think of cyber and AI and space as a nice cheap way of doing things,” he said.
“I don’t think this is necessarily the way to win a war. In the final analysis, wars end up killing people and you need kinetic killing capability.
“I’m quite happy to face someone down in a field if I’ve got a machine gun and he’s got a laptop.
“It all sounds wonderful but you still need that kinetic capability.”
The review of the armed forces will assess “Britain’s place in the world”, including its role in aid, development and counter-terrorism, in the biggest shake-up of its kind since the Cold War.
It will also look at how the UK can "better use technology and data to adjust to the changing nature of threats we face, from countering hostile state activity to strengthening our Armed Forces".
Mr Johnson has hired a King’s College London historian, John Bew, to conduct the review from Downing Street.
Dominic Cummings, the Prime Minister’s chief advisor, is said to have taken a personal interest in restructuring defence capability.
In a blog post last March, Mr Cummings described the military procurement process as a "farce".
He accused the military of having "continued to squander billions of pounds, enriching some of the worst corporate looters and corrupting public life via the revolving door of officials/lobbyists".