Former defence secretaries and senior military figures have warned Prime Minister Sir Keir Starmer that the UK faces a “1936 moment” and must urgently increase defence spending to 5 per cent of GDP to deter global conflict. In an open letter published in The Telegraph, the signatories—including ex-defence secretaries Sir Ben Wallace, Sir Grant Shapps and Sir Michael Fallon, former MI6 head Sir Richard Dearlove, and retired military chiefs—argue that Britain’s armed forces have been “hollowed out by years of chronic underfunding”.
The letter contrasts sharply with Sir Keir’s current pledges: 2.5 per cent of GDP next year and 3 per cent after the next election. It states: “Our actions fall dangerously short of matching this rhetoric and of meeting our treaty obligations. We are deluding ourselves if we believe Russia and our other adversaries are unaware of this.” The signatories urge the prime minister to “commit now to a bold, credible and measurable path to spending 5 per cent of GDP on core defence”.
The warning comes amid reports that the Ministry of Defence faces a shortfall of up to £28 billion—nearly half its annual budget—simply to make the armed forces “war-ready”. The letter accuses the government of heaping “unfunded new costs” onto the MoD, citing the Chagos Islands deal, pay rises and potential compensation for an Afghan data leak. The government has yet to publish its delayed defence investment plan (DIP).
In June 2025, Sir Keir pledged to meet NATO’s target of spending 5 per cent of GDP on national security by 2035, with 3.5 per cent on “core defence” and 1.5 per cent on “resilience and security”. The BBC has reported that the prime minister is considering bringing forward the 3 per cent target to 2029. Sir Keir did not confirm this but said Europe needed to “step up when it comes to defence and security”, citing the ongoing threat from Russia.
A government spokesperson defended the record, stating: “We are delivering the largest sustained increase in defence spending since the Cold War, with an additional £5bn this financial year alone and £270bn across this Parliament – ensuring no return to the hollowed out armed forces of the past.” The spokesperson added that the government was “well on track” to meet the NATO commitment.
