Military veterans aged 65 face being mobilised under new powers to prepare the Armed Forces for war.
The Government is set to increase the age at which the nation’s pool of retired soldiers, known as the strategic reserve, can be called upon from 55 to 65.
The new measures are being introduced as part of a new Armed Forces bill, which will be published in Parliament later.
The changes will make it easier to mobilise tens of thousands of former military personnel.
The Army has shrunk to its smallest number in more than 200 years, with just over 70,000 full-time, fully-trained troops ready to deploy to the frontline.
Under existing rules, the pool of retired soldiers can be called upon in the event of “national danger, great emergency or attack in the UK”.
However, under the new changes, this will be lowered to “warlike preparations”, which is already the threshold for reservists who have recently left the Armed Forces.
The measures come amid fears Britain could be dragged into a full-scale war with Russia in a matter of years.
Defence and security chiefs have repeatedly warned of the potential for large-scale war in recent months.
Al Carns, the Armed Forces minister, said just before Christmas that war was “already knocking on Europe’s door” and that Britain had to be prepared for a conflict that was “bigger” than those fought in Iraq and Afghanistan.
Last week, the UK announced it would be deploying troops to Ukraine, alongside France, if and when a ceasefire deal between Moscow and Kyiv is agreed.
While it is unclear exactly how many troops could be involved, reports have suggested up to 7,500 UK personnel could be deployed.
If this figure is accurate, it would effectively mean that around 21,000 personnel would be committed to Ukraine – with one cohort deployed, another in training and a third recovering for operations there.
However, military analysts have warned such a deployment would stretch the Armed Forces and would effectively become an “all of Army effort” to maintain.
Sources at the Ministry of Defence have pushed back against suggestions that 7,500 troops could be deployed, with insiders saying it could be lower.
£28 billion funding black hole
On Friday, the Government pledged to spend £200m to upgrade armoured vehicles and buy new kit in preparation for the peacekeeping mission.
The proposed changes would come into force next year if approved by Parliament, the BBC reported.
The Government estimates there are around 95,000 people within the strategic reserve, including veterans from the Royal Navy, Army, and RAF.
These are different to the reserve forces, which comprise personnel who volunteer part-time to serve in the military. Currently, there are almost 32,000 active reservists across the three wings of the Armed Forces.
The military has struggled to recruit and retain personnel in recent years. The Army has suffered the most, having shrunk from more than 100,000 personnel in 2010 to just over 70,000 now.
The most recent figures show a very marginal increase in the number of people joining the military. But it is still at its lowest ebb since the Napoleonic Wars.
Meanwhile, the Armed Forces is grappling with a £28 billion funding black hole over the next four years despite plans to boost defence spending.
Sir Keir Starmer was warned about the shortfall by the head of the military, Air Chief Marshal Sir Richard Knighton, a few days before Christmas.
On Monday, Sir Richard admitted Britain did not have the cash to deliver its military ambitions, which were set out by the PM in June as part of the Strategic Defence Review.
The Chief of the Defence Staff told MPs on the Commons defence committee: “I’ll be completely honest with you – we will not be able to do everything that we would wish to do as quickly as we might want to do it.
“If we wanted to do everything that’s currently in the programme and do all the extra things in the SDR [strategic defence review], could we do that with the budget that we have got? The answer’s no.”
UK not ready to defend itself
This is despite Sir Keir having announced last year that defence spending would rise from 2.3 per cent of GDP to 2.6 per cent by 2027. Looser pledges were also made in the strategic defence review to hit 3 per cent in the early 2030s and 3.5 per cent by 2035.
As part of the Strategic Defence Review, Sir Keir vowed to build 12 new nuclear attack submarines and spend billions more on new defence technology.
Britain’s military spending is the subject of increasing criticism, with a parliamentary report last year warning the country was not ready to defend itself against attack.
Earlier this month, the UK fell down the global defence spending rankings, and is now Nato’s 12th-biggest spender in terms of GDP compared with third in 2021.
News of the latest shortfall is said to have prompted Sir Keir to order a key MoD document, the defence investment plan, to be overhauled.
The Defence Investment Plan, which will set out how the Government’s long-term defence plans will be paid for, was originally due to be published in the autumn. However, it now appears to be stuck in financial purgatory, with Sir Richard telling MPs the MoD “do not have a date” for when it will be released.
It prompted concerns that the Armed Forces could soon be forced to make sweeping cuts to balance the books.
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