Britain’s Armed Forces aren’t ready to fight a war against a military with similar capabilities, the authors of Britain’s Strategic Defence Review have warned.
In a stark assessment, the report said that our forces are better suited ‘to a peacetime era’ and are ‘not currently optimised for warfare against a “peer” military state’.
The externally-led Strategic Defence Review (SDR), written by former Nato secretary general Lord Robertson, retired general Sir Richard Barrons and Russia expert Fiona Hill, was described as the most profound change to defence in 150 years.
While it leaned heavily into new technologies, it has also recommended an increase in the size of the regular Army from 73,000 to 76,000 in the next Parliament.
This follows decades of the Army shrinking from 156,000 at the end of the Cold War. The review also includes a chilling list of the potential effects of conflict on the UK’s way of life and lays bare Britain’s overseas dependencies and threats.
In the event of war, Britain would be subject to attacks on its military bases at home and abroad, long-range drone and cruise missile sorties, cyber-attacks crippling national infrastructure and disruptions to economic interests and international trade routes.
The SDR states that the defence medical services couldn’t cope with a mass casualty event and that the military is suffering from a recruitment crisis which means only a small number of troops could be deployed.
The document added: ‘The UK is entering a new era of threat and challenge. The West’s long-held military advantage is being eroded as other countries modernise and expand their armed forces at speed.’
A Gunner from B Company the 3rd Battalion, The Parachute Regiment, engages enemy positions with the general purpose machine gun (GPMG) during the combined arms live-fire exercise (CALFEX) phase of Exercise Swift Response on the 4th of May 2024
Eurofighter Typhoon jets from the UK’s Royal Air Force land at Murted Air Base in Ankara for inspection by Turkish officials on December 18, 2024
Handout photo dated 28/04/25 issued by the Ministry of Defence (MoD) of vessels during Operation Highmast as they make their way to the western Pacific Rim via the Mediterranean and Middle East to conduct interoperability training and defence engagement
This officer from the Rifles moving quickly through the water, keeping low whilst moving to another target during a live attack in Brecon
The report also reveals that 95 per cent of the UK’s data is carried by undersea cables that are vulnerable to attack and that the UK relies on imports for 46 per cent of its food.
It stated: ‘Undersea pipelines and data cables are critical for sustaining daily national life. The maritime domain is increasingly vulnerable. The Royal Navy must be prepared to deter maritime incidents similar to the sabotage of the Nord Stream 2 gas pipeline and the cutting of undersea data cables in UK and international waters.’
In the year to September 2024, the UK suffered 89 nationally significant cyber-attacks. The Navy and RAF conducted 374 escorts of Russian Federation vessels between 2020 and 2024.
In that same period there were 32 launches of RAF Typhoon Quick Reaction Alert aircraft.
The report added: ‘Defence must prepare for a much more difficult world of heightened competition, more frequent crises and conflict that sees conventional military attacks combined with intensified sub-threshold aggression.
‘The UK is already subject to daily sub-threshold attack, targeting its critical national infrastructure, testing its vulnerabilities as an open economy and global trading nation and challenges its social cohesion.
‘Changes in the strategic context mean that UK defence must plan on the basis that Nato allies may be drawn into war with – or be subject to coercion by – another nuclear-armed state.’
The SDR will bring about a transformation of the Armed Forces, including the development of a so-called Integrated Force, a coming together of the separate services.
Members of the Welsh Guards prepare a general-purpose machine gun (GPMG) ahead of a visit by Prince William on November 26, 2024 in Wiltshire, England
Eurofighter Typhoon jet from the UK’s Royal Air Force lands at Murted Air Base in Ankara for inspection by Turkish officials on December 18, 2024
While defence chiefs are determined to meet the Prime Minister’s challenge to become ‘war ready’, the SDR reveals they are also expected to make savings.
The Army is expected to deliver ‘a ten-fold increase in lethality’ – but without a significant number of regular soldiers, although the report concedes there is a ‘strong case for a small increase in regular numbers when funding allows’.
The SDR suggests fewer paratroopers will be trained to jump. The report calls on the RAF to become more efficient and use civilian planes when a task ‘does not require military capability’.
The Royal Navy is expected to move towards a ‘cheaper’ fleet. Admirals are expected to use ‘commercial vessels’ for transportation in non-contested environments and to share logistical challenges with allies.
The UK’s £7 billion combined-cost aircraft carriers are expected to become more versatile, with adaptations to ensure long-range missiles can be fired from their decks and more uncrewed aircraft.
Defence Secretary John Healey said: ‘We must move to war-fighting readiness, to avoid the huge costs that wars create. We prevent wars by being strong enough to win them.
‘We will establish a new hybrid-Navy, our carriers will carry the first hybrid airwing in Europe. We will create a British Army which is ten times more lethal, with an aim of 76,000 regular soldiers in the next parliament.
‘We will also increase the number of cadets by 30 per cent and develop a new strategic reserve by 2030.’
The SDR has made 62 recommendations which government ministers have pledged to implement in full.
