UK military chief writes to PM amid worry over defence spending plan

The UK's military chief has written to the prime minister amid concerns that an offer of around an extra £13bn to fund a major investment plan for defence is not enough, Sky News understands.

The content of the letter from Air Chief Marshal Sir Richard Knighton is not known, but the fact he felt the need to put his thoughts in writing signals the seriousness of the challenge faced by Sir Keir Starmer as he attempts to finalise the long-delayed defence investment plan.

The highly unusual move came after the Treasury is understood to have offered the Ministry of Defence (MoD) around an additional £13bn over four years to help fund the purchase of new jets, submarines, ships, drones and missiles.

This is at the lower end of a range of between £12bn and £18bn that had been under consideration – and far short of the actual sum of extra money that the military believes it needs to rebuild its hollowed-out ranks at a time of escalating threats.

One source said Sir Richard met with fellow military chiefs to discuss the proposed settlement on Monday.

The source said there is thought to have been dissatisfaction expressed by at least one of the service chiefs who were present about the inadequacy of the amount.

That has not been confirmed, however.

The wait goes on...

Whatever went on behind closed doors, an earlier anticipation that the defence investment plan would finally be published this week subsequently evaporated.

By Wednesday evening, discussions between the MoD, Treasury and Number 10 were still said to be "live" even though the prime minister had been expected to speak about defence and offer some headline figures on his push to rearm this Friday.

That appears designed to coincide with an anticipated announcement on the opening of a new, vast drone testing centre – as reported by Sky News earlier in the week – in Swindon.

It is not clear, though, whether the event will still go ahead even though invitations are thought to have been issued to a number of start-up drone companies to attend.

The extraordinary display of confusion and paralysis at the heart of government over what is meant to be a strategic priority – the defence of the nation – has left officials inside the MoD, the military and defence industry slack-jawed.

John Healey, the defence secretary, was asked whether he would accept anything less than an £18bn uplift.

Speaking at a joint press conference with the foreign secretary and their respective Australian counterparts, he declined to talk about specific numbers but indicated that Sir Keir was listening.

"The prime minister knows what defence and the nation need," Mr Healey said.

"He is set to make his announcement soon."

UK under mounting pressure

A gap in funding to rebuild the Royal Navy, army and Royal Air Force was already thought to be at least £28bn before new expectations were added following the publication of a sweeping view of defence last June.

Upping the pressure is wider war in the Middle East and increased demands by Donald Trump for the UK and other European NATO allies to take up a much greater level of responsibility for their own defences.

The UK presents itself as a leading member of the alliance.

Yet it does not plan to hit a new NATO target to increase defence spending to 3.5% of GDP from the UK's current level of around 2.3% until 2035 – the furthest possible date that allies set to achieve the new funding baseline.

Some other countries are moving a lot faster.

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Last year's Strategic Defence Review was meant to be the defining document on the armed forces of the Starmer government, outlining the prime minister's stated desire to rearm.

It should have been followed last autumn by the defence investment plan, which would explain how the vision would be funded.

But disagreement on the size of the uplift meant the publication date has been repeatedly pushed back.

The prime minister has promised to release it before a NATO summit on 7 and 8 July.

Asked previously about the defence investment plan, a MoD spokesperson has said: "The defence investment plan will deliver the best kit into the hands of our armed forces. We are working hard to finalise it, and it will be published as soon as possible."

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