UK Defence Secretary John Healey abruptly resigned on the 11th (local time). Citing insufficient defence funding, a sitting defence secretary stepped down while openly criticising the prime minister and the Treasury. As the security threat from Russia grows and pressure from the North Atlantic Treaty Organization (NATO) to raise defence spending intensifies, open dissent erupted even within the ruling Labour Party that “the current level of investment cannot protect national security”.

At the heart of the situation is a dispute over the size of the increase in defence spending. In his resignation letter, Healey stated that “the government and the Treasury are not providing the resources needed to defend the nation against mounting threats,” adding that “the current level of the Defence Investment Plan (DIP) cannot be accepted”.

He specifically cited a recent warning by Prime Minister Keir Starmer that “Russia could attack a NATO member state before 2030,” and criticised that “while acknowledging the threat, the necessary funds are not being provided”. He further argued that “under the current plan, military readiness will be weakened, the risks to personnel in operations could increase, and ultimately national security will be undermined”.

Local media including the BBC reported that, during the resignation process, he strongly criticised that “the Treasury lacks will and the Prime Minister lacks competence”.

Along with Healey, Deputy Defence Minister Al Kans also resigned. In his resignation statement, Kans said that “we need a new way of governing”. Two aides to Healey also stepped down. It is being described as the largest collective departure in the security field since Labour took power.

Security Minister Dan Jarvis was appointed as the new Defence Secretary.

The UK government faced criticism for recognising the need to increase defence spending yet failing to reflect it in the budget.

Upon taking office, Prime Minister Starmer launched a ‘Strategic Defence Review (SDR)’ aimed at reforming the British armed forces. The SDR report stated that military modernisation and force enhancement were needed. Based on this, the planned increase in defence spending would rise only modestly from 2.6% of gross domestic product (GDP) in 2027 to 2.68% in 2030. Healey had demanded that this be expanded to at least 3%. Richard Barrons, a former army general who served as an independent reviewer of the report, told the Guardian that “the government did not properly allocate the funding required in the defence review it commissioned itself”.

The Treasury maintains that a large expansion of defence spending is difficult amid economic slowdown and fiscal pressures. With demand for welfare, education, and health budgets rising simultaneously, it argues that tightening on defence spending is unavoidable in order to maintain fiscal soundness.

The Guardian analysed that Prime Minister Starmer exacerbated the conflict by delaying decisions. He put off the defence budget issue until the last moment and ultimately pressured Healey to accept the existing plan, which directly triggered the resignation.

On the surface, the dispute is a disagreement over increasing defence spending, but some argue that the root cause lies in the communication capacity of the Starmer government. The Guardian assessed that the Starmer government failed to sufficiently explain to the public the escalating security threats from Russia and China and the need to expand defence spending over welfare budgets. Unlike welfare budgets, whose benefits voters feel directly, the security benefits from higher defence spending are less tangible, so the government should have explained and persuaded more actively.

In an editorial that day, the Guardian wrote that “the West faces the most dangerous security environment in decades, yet the Starmer government has not yet crafted a compelling case for why more defence spending is needed”.

This episode appears likely to deal a mortal blow to the leadership of Prime Minister Starmer, who has been pushed to the brink. Starmer took office after leading Labour to a landslide in July 2024, but his approval ratings plunged amid disappointment with governance on the economy, welfare, and immigration policy. In particular, after Labour suffered a crushing defeat in local elections last month, a wave of calls for accountability led to demands for his resignation. The Guardian reported that even within Labour, Starmer is being judged politically to be beyond a ‘lame duck’ and in a ‘terminal state,’ and that some ministers have recently advised him to consider his position.

The timing of the resignation by Healey is also poor. Prime Minister Starmer will attend the Group of Seven (G7) summit next week, and next month a NATO summit with United States President Donald Trump in attendance is scheduled. Former UK Chief of the Defence Staff Nick Carter said in a BBC interview that “the timing could not be worse”.