The UK government’s defence investment plan (DIP) will guide the spending decisions of the Ministry of Defence and armed forces not only for the remainder of this parliament, but also for the five years from 2029. So far, the plan has been praised and criticised in equal measure. But one element that has attracted widespread attention is the overall spending figures.

Part of the settlement that has been agreed with the Treasury rests on the Ministry of Defence (MoD) finding around £11 billion in efficiency savings between now and the end of the financial year in 2030. This will be a significant challenge – but efficiency details like these are often used in government funding calculations to increase the headline figure.

There will be an additional hurdle for the new chancellor however: there is still a a shortfall of around £4.5 billion in the funding available against the expected spending, even once the savings have been factored in. This will have to be found before the next general election if the commitment to spend 2.7% of GDP on defence from 2027-2028 is to be met.

Andy Burnham has said that if he becomes the UK’s next prime minister he will not deviate from either the current plan or the longer-term policy for the UK to spend 3.5% of........

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