UK Defence Secretary Dan Jarvis has called on Andy Burnham — Labour's prime minister-in-waiting — to commit to a sharply accelerated defence spending trajectory from 2030, explicitly asking him to "evidence the trajectory" toward NATO's 3.5% of GDP target. The remarks, made ahead of the NATO summit in Ankara opening on Tuesday, 7 July, put public pressure on Burnham to go materially beyond the 2.68% of GDP floor to which Keir Starmer's government has committed by 2030, per The Guardian.

The 3.5% figure is not hypothetical. It was agreed in 2025 under sustained pressure from US President Donald Trump and, at current economic scale, would require approximately £25bn a year more for the UK military by the mid-2030s than is currently planned. Jarvis said he would personally reassure US Defence Secretary Pete Hegseth at the summit that the UK intends to meet that pledge — a bilateral signal as much as an alliance-wide one.

The backdrop is contested. John Healey resigned as defence secretary in June 2026 precisely because Starmer would only lock in 2.68% by 2030, not a steeper climb toward 3.5%. His departure was public and pointed. Jarvis, a former paratrooper who succeeded Healey, has moved quickly to stabilise the narrative: he secured an additional £1.5bn over four years — earmarked partly for drone procurement — as part of the broader £298bn four-year Defence Investment Plan published in the week ending 6 July, after what Whitehall sources described as months of ministerial wrangling.

That plan was formally announced on 30 June in Berkshire, with Starmer on the platform. It allocates £5bn specifically for drones and amounts to roughly $20bn in additional spending, funded in part by cutting investment budgets elsewhere — road and energy projects among them. Jarvis called the trade-offs "difficult but necessary." Reuters noted the drone allocation in particular; the broader funding mechanism drew immediate scrutiny.

That scrutiny sharpened within 48 hours of the announcement. A Reuters analysis published on 1 July identified a residual £4.7bn ($6.2bn) funding gap that Burnham would need to close on taking office. Al Jazeera reported separately that questions were already being asked about whether Burnham had been fully briefed on the scale of the challenge before it became public. Burnham's own response, in a 2 July interview, was direct: he said he would "fully fund" the Defence Investment Plan and there would be "no compromise on the security of the nation." Whether that formulation extends to the post-2030 trajectory toward 3.5% — or covers only the existing DIP envelope — is exactly the ambiguity Jarvis is now pressing him to resolve.

Jarvis confirmed he has already been in contact with Burnham and his team, discussing defence priorities and the specifics of the DIP. That channel is significant. It suggests coordination rather than confrontation, even as the public framing from Jarvis carries unmistakable urgency.

The Ankara summit adds immediate diplomatic weight. Jarvis travels with Starmer and Foreign Secretary Yvette Cooper. The agenda is thick with burden-sharing politics: Trump's sustained pressure on European allies to hit 3.5% has made summit optics consequential for domestic credibility as much as alliance management. NATO Secretary-General Mark Rutte said on 29 June that he was "confident" Burnham would honour the UK's spending commitments — a statement calibrated to reinforce, not just endorse.

Operational commitments are also stacking up. The UK is preparing a significant sustained deployment to safeguard the Strait of Hormuz in a joint operation with France. Jarvis described the current security environment as "absolutely more dangerous and more complicated than at any point during my lifetime" — words that carry particular weight from a former paratrooper with operational experience, and that frame the 3.5% conversation as something more than internal party arithmetic.

The structural question for Burnham is fiscal. Hitting 3.5% of GDP in the mid-2030s would require defence spending roughly £25bn a year above current plans, on top of absorbing the £4.7bn gap already identified in the existing DIP. The funding sources are not specified. Cuts to other investment budgets — the mechanism used by Starmer for the current uplift — have already drawn pushback from infrastructure and energy lobbies. Tax rises and additional borrowing both carry political costs that Burnham's team has yet to publicly price in. Jarvis's call to "evidence the trajectory" is, in that sense, a demand for a credible fiscal path, not just a rhetorical commitment. The Ankara summit is where the UK will need to begin answering that question in front of its most exacting audience.