UK Defence Secretary Dan Jarvis announced on 23 June 2026 that the government will raise defence spending to 5% of GDP by 2035. He made the statement at the RUSI Land Warfare Conference, a gathering focused on ground combat capability that draws senior military leaders, defence officials, and allied representatives.

The 5% target was first reported by the BBC on 18 June. If achieved, it would place the UK among NATO's highest-spending members relative to the size of its economy — a tier currently occupied by only a handful of allies, none of them in Western Europe at that level. The UK currently spends about 2.3% of GDP on defence, so reaching 5% by 2035 demands substantial annual increases across two spending review cycles. This trajectory will likely force difficult structural choices: how to grow troop numbers, whether to accelerate weapons programmes, how to build ammunition reserves, and how to balance spending between equipment and operational readiness.

The choice of venue was deliberate. Land warfare is where Europe's security anxieties have become most urgent since 2022, particularly given the conflict in Ukraine. By speaking there, Jarvis signalled that this commitment goes beyond a headline budget figure—it connects to concrete capability questions: armoured vehicles, artillery, stockpiles, and the capacity to field larger forces.

The Ankara NATO summit provides the immediate diplomatic context. NATO heads of state will face pressure, particularly from the United States, over the gap between the alliance's defence spending benchmarks and what member states actually contribute. Britain's 5% pledge is a direct move to position London as a serious contributor to these discussions and to strengthen its voice in debates about NATO's eastern flank and how the alliance deters Russia.

The strategic logic beneath this announcement reveals a larger shift. The British Army has contracted steadily over the past decade. The 2021 Integrated Review and its later refresh further reduced regular army numbers and postponed major weapons programmes. A genuine 5% commitment—not achieved through accounting tricks—would need to reverse this trend: growing personnel, accelerating programmes like the Ajax armoured vehicle, funding advanced weapons systems, and addressing the ammunition shortages that Ukraine has exposed as a critical NATO weakness.

There is reason for caution about whether this target will hold. British defence spending targets that extend beyond a single parliament have a mixed track record. The existing 2% NATO commitment itself was partly reached by including spending categories outside traditional force investment. Analysts will ask whether the government's definition of 5% includes intelligence, cyber operations, nuclear forces, and veterans' programmes—items that can inflate the headline without adding combat capacity.

For allied capitals—Warsaw, Tallinn, Washington—the signal matters significantly. The UK is one of only two nuclear-armed European NATO members and the alliance's second-largest European defence spender in absolute terms. A credible, long-range spending commitment from London strengthens the case for a wider European defence increase and gives diplomatic weight to the Ankara summit, which will otherwise be dominated by disputes over contributions.

What emerges from Ankara in formal language, and whether other European allies make comparable commitments, will determine how much weight this announcement carries. The 5% target is the foundation. The architecture around it is still under construction.