Prime Minister Keir Starmer has signed a landmark agreement committing British troops to Ukraine should a peace deal with Russia be struck. The pledge, made alongside France, marks a significant shift in the UK's stance. However, it has been met with immediate scepticism and serious questions about whether Britain's diminished armed forces can fulfil such a promise.
Scepticism and Strategic Doubts
The announcement, made on Thursday 08 January 2026, was swiftly criticised by political opponents and defence analysts. Reform UK leader Nigel Farage derided the commitment, asking pointedly, "With what boots? What kit?" He argued the UK was in "no position" to deploy ground forces to Ukraine, suggesting any effort might only be sustainable for six to eight weeks.
Military experts echo these concerns. Sir Richard Shirreff, a former deputy commander of NATO, stressed that any deployment would require substantial numbers—potentially as many as 50,000 personnel—and must be ready for combat. "There's not going to be a peace until Russia is forced into it," he told LBC, emphasising the need for a force with "the right capability" and "the right numbers."
The Stark Numbers Behind the UK's Armed Forces
Current government figures reveal the scale of the challenge. The UK's total armed forces number approximately 147,000 personnel, with just over half assigned to the Army. This places Britain far behind global powers and even many mid-sized nations in terms of sheer manpower.
All three service branches are currently under strength. The Army is below its target size by 3%, the Royal Navy by 8%, and the Royal Air Force by a significant 13%. This follows a trend that saw the UK's military in 2021 reach its smallest size in four centuries.
Stuart Young, a former Royal Navy officer and visiting fellow at Cranfield University, provided a sobering analysis. He estimates that sustaining a frontline force of 10,000 troops in Ukraine would actually require a total of 30,000 personnel, once rotation, training, and support are factored in. This would consume over 40% of the entire British Army and could only be maintained briefly before crippling other defence commitments.
Equipment: Quality Versus Quantity and Age
The Ministry of Defence's latest equipment inventory, accurate to April 2025, paints a picture of a technologically advanced but stretched and ageing arsenal.
On land, the forces possess 3,955 major combat equipment pieces. This includes 288 Challenger 2 main battle tanks and over a thousand other armoured fighting vehicles. However, many vehicles are decades old, with some dating back to the 1960s. The troubled Ajax vehicle programme has been delayed by technical issues, and the Challenger 3 upgrade programme has reduced the number of available tanks.
At sea, the Royal Navy operates 70 vessels, including nine submarines (five of them nuclear-powered). A significant concern is the age of the fleet; the oldest Type-23 frigates are over 30 years old, well beyond their intended lifespan, with replacements long delayed.
In the air, the RAF has 504 fixed-wing aircraft, including 129 Typhoon jets, and 276 helicopters. While modern aircraft are highly capable, their complexity and cost mean numbers are limited.
Mr Young notes that donating older equipment to Ukraine has created "gaps in the UK's capabilities," and much of the remaining kit "requires significant maintenance" to be deployment-ready.
Spending Promises and the Long Road to Recovery
In response to these challenges, the government has announced major spending increases. Chancellor Rachel Reeves boosted defence spending to 2.6% of GDP for the coming year. Prime Minister Starmer has committed to reaching 2.5% by April 2027, with an ambition to climb to 3% in the next parliament.
In cash terms, spending is projected to rise from £60.2bn in 2024/25 to £73.3bn by 2028/29. A new Armed Forces Recruitment Service (AFRS) is also slated for launch in 2027, backed by a £1.3bn investment, aimed at streamlining hiring and tackling a retention crisis.
Despite these pledges, experts caution that rebuilding military capacity takes years. Stuart Young estimates it would take at least two more years before any significant increase in troop numbers could be felt on the front line. The Prime Minister's historic commitment to Ukraine, therefore, hinges on a rapid and successful reversal of the UK's military decline—a task that will test the government's resolve and the nation's resources in the years ahead.
