Conservative leader Kemi Badenoch has criticised Prime Minister Sir Keir Starmer over what she described as a significant funding gap in the UK’s new defence investment plan, arguing that it leaves an “unfinished mess” for his expected successor, Andy Burnham.

The government has announced a £15bn boost to defence spending up to 2030, aimed at strengthening the UK’s military readiness in response to growing global security threats.However, ministers have acknowledged that around £4.7bn of the funding required has not yet been identified and will need to be addressed in the upcoming autumn Budget.

During Prime Minister’s Questions, Badenoch questioned whether Burnham, widely tipped to replace Starmer as prime minister on 20 July, had agreed to the financial commitments underpinning the plan.Starmer rejected the criticism, accusing the Conservatives of hypocrisy and highlighting past cuts to defence spending under their administration.

He defended the plan as necessary for national security and said funding would be achieved through reallocations within departmental budgets rather than increased borrowing.Defence Minister Luke Pollard confirmed that the next chancellor would need to resolve the £4.7bn shortfall, describing it as a standard fiscal process.Meanwhile, Treasury savings of £10.3bn have been identified, but further reductions will be required across government departments, including transport and energy.Some road and rail projects face potential cancellation, prompting backlash from local MPs and regional leaders.

Opposition parties, including the Liberal Democrats, warned that the shortfall could leave the UK vulnerable, while government officials insisted that frontline NHS services would be protected.

The debate highlights growing political tension over defence priorities, fiscal constraints, and the financial challenges awaiting the next leadership team.