British Defence Secretary John Healey stepped down on Thursday following a disagreement on military outlays, charging Prime Minister Keir Starmer with not allocating sufficient government funds to protect the nation during a period of growing dangers.

The surprise departure, paired with a sharply worded public statement, adds to the strain on Starmer as he confronts a possible leadership contest and highlights the core government dilemma of boosting defence outlays when budgets are tight.

Britain's defence and finance departments have spent months negotiating ways to address growing calls for higher military spending, which has postponed release of the country's Defence Investment Plan originally slated for last year.

Service chiefs have emphasised that the plan is essential to counter elevated threat levels amid repeated Russian approaches to British waters, yet the administration is already working to cut debt while taxes stand at their highest in decades.

The prominent exit occurs as Starmer fights to retain control after Wes Streeting left as health minister in May and rival Andy Burnham seeks a return to front-line roles to mount a leadership challenge.

You have been unable, and the Treasury has been unwilling, to commit the resources that the nation needs to defend the country at this time of rising threats, Healey said in his letter to Starmer.

British defence minister resigns over Starmer's slow-walking of defence funds

The nation's defence sector has grown frustrated with the postponement of the plan, noting it blocks investment in extended programmes.

The UK faces a United States shifting focus from Europe while the US-Israeli conflict with Iran revealed Britain's limited military preparedness, as its navy could not quickly send an advanced vessel to the area.

The defence plan seeks to detail funding for equipment and services so forces reach warfighting readiness, and Starmer stated on Wednesday it would appear ahead of a NATO summit starting July 7.

Your DIP financial settlement, which I was first given in full on Monday afternoon this week, falls well short of what is required for defence and the country at this dangerous time, Healey said.

I am being forced to make decisions that would reduce the readiness of our forces and increase the risk to personnel on operations, and could make the country less safe.