The clock is ticking toward the Nato summit in Turkey. With less than three weeks until the alliance gathers, the British government has made a definitive choice: the long-awaited defence investment plan will be published, regardless of the political vacuum at the top.

Sir Keir Starmer announced his resignation as prime minister and Labour leader on Monday. He remains in office during the transition, but his authority is fading. Despite this, Downing Street confirmed the defence strategy will proceed. It is a high-stakes gamble. The plan has already cost the government two defence ministers, including Al Carns, who quit last month in protest.

A Plan Under Fire

The core of the controversy lies in the numbers. While the government has promised to reach 3.5 percent of GDP for defence spending by 2035, the current roadmap remains a point of intense friction. Former Defence Secretary John Healey argued that a planned increase to 2.68 percent fell "well short" of the 3 percent target he deemed necessary for national security.

Reports suggest the Ministry of Defence requested an additional £28 billion through the end of the decade. The Treasury, however, has reportedly offered only £10 billion. To bridge the gap, Starmer has ordered other government departments to slash their investment budgets. It is a zero-sum game.

John Healey Warns UK Defence Spending Falls 'Well Short'

The Shadow of a Successor

This decision creates an immediate headache for whoever replaces Starmer. Andy Burnham, the MP for Makerfield, is currently the only formal candidate in the leadership race. He has previously suggested that welfare reform could unlock more funding for the military. If he wins, he may choose to scrap or rewrite the plan entirely.

"There will now be a change of prime minister," Defence Secretary Dan Jarvis said at the Rusi Land Warfare Conference. "There will be no change in the urgent need to produce the defence investment plan." Jarvis is walking a tightrope. He needs to satisfy Nato’s demand for "clear, concrete and credible" spending commitments while managing a government that is effectively in caretaker mode.

Credibility on the Line

Nato Secretary-General Mark Rutte has been clear about his expectations for the 7 July summit. The alliance is under pressure to bolster its budgets following Russia’s invasion of Ukraine and the return of Donald Trump to the US presidency. Trump has repeatedly warned that American protection is contingent on European spending.

Conservative shadow defence secretary James Cartlidge seized on the uncertainty in the House of Commons this week. He questioned who is actually in charge of the nation’s security during this transition. It is a fair question. The government is pushing a policy that its own ministers have resigned over, and which the next prime minister may immediately discard.

Key Takeaways

  • The government will publish its defence investment plan before the 7 July Nato summit, despite Sir Keir Starmer’s resignation.
  • The strategy faces internal opposition, having already triggered the resignations of two defence ministers over funding levels.
  • The next prime minister will inherit a policy that may be at odds with their own fiscal priorities, creating potential for further delays.

For now, the civil service is preparing briefings for leadership candidates. The transition is meant to be orderly. Whether the defence plan survives the change in leadership remains the most significant test of that order.