ACM Sir Rich Knighton CDS speaks at defence futures forum — Chief of the Defence Staff Air Chief Marshal Sir Rich Knighton is said to have warned the Prime Minister about the shortfall before Christmas (Picture: MOD)

Tri-Service

Demands on defence are rising following reports of £28bn shortfall, MOD warns

The Ministry of Defence says demands on defence are rising, amid reports of a £28bn shortfall in the defence budget.

It comes as The Times reports that the Chief of the Defence Staff told the Prime Minister about an MOD assessment made last year which showed a £28bn shortfall between now and 2030.

Air Chief Marshal Sir Rich Knighton is due to appear before MPs on the influential Defence Committee on Monday, where he will no doubt face questions about the state of the MOD’s finances and its ability to implement the Strategic Defence Review.

This will be the Committee’s first opportunity to question ACM Sir Rich since he became head of the Armed Forces.

An MOD spokesperson told BFBS Forces News: "The UK defence budget is rising to record levels as this Government delivers the biggest boost to defence spending since the Cold War, totalling £270bn this Parliament alone.

"Demands on defence are rising, with growing Russian aggression, increasing operational requirements and preparations for a Ukraine deployment."

Matthew Savill is director of military sciences at the Royal United Services Institute.

Reacting to the £28bn figure on X, he said it sounded "quite high" but "plausible".

"This figure is apparently over four financial years, so around £7bn a year, for a defence budget of just over £281bn in total," he noted.

What this all means is that this gap is plausible. But the MOD is not suddenly 'broke' (it's getting over £62bn a year still). Rather, there is now a growing gap between the urgent rhetoric around rapid rearmament, and the more leisurely pace of investment.
— Matthew Savill (@MTSavill) January 8, 2026

The Defence Investment Plan, which is expected to set out the details of how the Strategic Defence Review will be delivered, had been expected to be published before Christmas. The Times reports it may now be delayed until March.

An MOD spokesperson said: "We are working flat out on the Defence Investment Plan, which will fix the outdated, overcommitted and underfunded defence programme we inherited."

A Government source said the UK iwa "on track" to fulfil the commitments outlined in the SDR.

Back in December, Defence Secretary John Healey told BFBS Forces News the Defence Investment Plan would be published as soon as possible

ACM Sir Rich took over as Chief of the Defence Staff in September and is responsible for the delivery of the Strategic Defence Review published in June, as the UK has pledged to boost defence spending to 2.5% of GDP by 2027.

The SDR also set out a goal to raise spending to 3% in the next Parliament "when fiscal and economic conditions allow".

The news of a shortfall comes as the UK pledged to put troops on the ground in Ukraine in the event of a ceasefire, and after UK bases and military personnel supported a US operation to seize an oil tanker in the Atlantic, said to be part of a shadow fleet seeking to evade sanctions on Iranian oil.