Starmer says the "very nature of conflict is changing before our eyes," before referencing the war in Ukraine.

He says that despite having limited resources, Ukraine has managed to destroy the Black Sea fleet, strike deep into Russia and stop its army from advancing.

Starmer says Ukraine has done that not only through "sheer courage", but also by embracing technology.

"Innovating at speed and scale is more important than ever," adding that AI will "accelerate that further".

In that context, he says, Nato remains "more important than ever," adding that in order to sustain the alliance, European nations must take "more primary responsibility for their own defence".

Starmer says his government has "reversed at last the corrosive hollowing out of our armed forces" and says the UK's defence programme has been "underfunded and unsuited" to the threats faced for too long.

The prime minister says these changes are being made not because the UK wants war, but to avoid it.

Prime Minister Keir Starmer starts by thanking "all of those that serve our country".

He says he meets people from all walks of life as PM, and says he knows how worried they are "about the state of the world".

"They're feeling tired at being at the mercy of events beyond our shores," Starmer says.

He says the human toll of international conflicts cuts across the UK's "values of justice" and the "simple British impulse that bullies and dictators cannot be allowed to push people around".

He adds that these threats "are not remote", but that foreign states are also targeting the UK.

Reeves continues her speech by paying tribute to Starmer.

She says the UK's defence has been a "defining pillar" of his leadership and his "moral clarity" against the threats the country faces will be part of his legacy.

Reeves calls Starmer her "friend" before introducing him to the stage.

After the defence secretary, Chancellor Rachel Reeves takes to the stage.

She says when she was shadow chancellor, she "wrote and spoke about the importance of security and resilience for economic growth", an approach she calls: "securinomics".

It's something she says has become more "valid" in her time as chancellor.

Reeves goes on to claim she has overseen the biggest uplift in defence spending "since the Cold War".

Reeves says there will be a further uplift today, "an additional £15bn worth of funding by again reprioritising spending across government".

She says "defence and readiness for now are not remote contingencies", instead being "an immediate and pressing requirement".

"By defending ourselves we defend our allies and values," she says.

Jarvis says he knows life in the armed forces isn't always easy, acknowledging there is "some way to go to improve service life", but says they have awarded three above-inflation pay rises, extended free childcare and improved military homes.

"Our personnel are today better supported and through this defence investment plan, we will make them better prepared," Jarvis continues.

He says the plan recognises the "hard truth" that the conflict in Ukraine "completely upended the way of war," saying that the plan invests a record amount in drone warfare, as well as more money for a hybrid navy and for the Royal Air Force.

Jarvis says it "reflects the realities of warfare" and commits to strengthening the UK's nuclear deterrent and continue supporting Nato.

He ends by reiterating that people remain the Army's "most important asset", adding: "This defence investment plan is for them."

Defence Secretary Dan Jarvis is first up to speak, he says there has been no "shortage of column inches or speculation" about the defence investment plan.

"But we shouldn't lose sight of what the defence investment plan is truly about, the measure of our security is the strength of those who defend it," he says.

He says the central purpose of the plan is to "get the kit and technology" the armed forces need now and for the "years ahead".

He adds that credit goes to Prime Minister Keir Starmer for getting the plan to where it is today.

"Under his leadership, Britain has proved itself a reliable partner and a trusted ally."

We're expecting to hear from Prime Minister Keir Starmer imminently as he makes a speech on the defence investment plan due to be released today.

We're also expecting to hear from Defence Secretary Dan Jarvis and Chancellor Rachel Reeves before the PM speaks.

We'll have updates throughout - and you can watch live at the top of the page.

Image source, PA Media

Conservative leader Kemi Badenoch has criticised the defence investment plan as being insufficient and "barely half what the armed forces say is needed".

Writing on social media, Badenoch says Keir Starmer is "underfunding our military in his search for a ‘legacy’".

She also questions if Andy Burnham, expected to be the next prime minister, "has signed off on this", adding that if he has, "then he too is culpable of putting our service personnel at risk with this weak plan".

Badenoch goes on to say: "We need to cut benefits to fund our armed forces."

For context: Some of the details from the defence investment plan have been released by the government, but the full document will be published later today.

Three key tests for the defence investment planpublished at 10:13 BST

10:13 BST

Frank Gardner
Security correspondent

Image source, PA Media

There are several tests that need to be applied to the defence investment plan once it is revealed in full today.

Does it meet Britain’s Nato commitments?

Britain, as a leading member of the transatlantic alliance, has joined other members in committing to raising defence spending to 3.5% of GDP by 2035.

Former Defence Secretary Ben Wallace says that is too late, that the threat from Russia is much more imminent.

Is it fit for the fast-changing pace of warfare?

Drones have transformed the way wars have been fought in Ukraine, Iran and the Caucasus.

The MoD has been accused of being slow to learn the lessons from those conflicts. But the refocussing of the defence investment plan towards drones and autonomous systems has gone some way to address this.

Is it enough money?

No, say military experts.

The full details have yet to be revealed but it is unlikely to be anywhere near the £28bn demanded by the departed Defence Secretary John Healey who resigned in protest at the insufficient funding.

Henry Zeffman
Chief political correspondent

The simple answer is we don’t know. But the political reality is that he will have to tell us soon enough.

There will be intense criticism from the government’s political opponents - as well as some Labour MPs - over the course of the day about the amount of money the government is committing.

The question of whether extra money should be spent, and if so how that extra money could be generated, will be a question for Burnham to address in less than three weeks.

If no other Labour MP makes a leadership bid, Burnham is expected to become prime minister on 20 July.

How does defence compare with other government spending?published at 10:03 BST

10:03 BST

By Anthony Reuben

This chart breaks down what the Treasury was planning to spend in the 12 months from April this year.

The largest category is what the Treasury calls “social protection” which covers things like the state pension and working-age benefits. More than £150bn of that £400bn is expected to be spent on the state pension, external.

If you add health spending on to social protection you have already covered about half of what the government is expected to spend.

Next comes education at £145bn, and then debt interest payments of £135bn on the money the government borrows.

Defence spending comes next at £90bn - which is about 6% of the government’s spending plans.

Tom Redman, CEO of British-based drone supplier Evolve Dynamics, says £5bn being invested in the use of drones is "really welcome".

Redman, whose company supplies drones to the British and Ukrainian armies, tells BBC Radio 4's Today programme: "Any modern Nato nation is now modernising their militaries with uncrewed systems, with autonomy at the heart of it."

Asked if the UK is self-sufficient, Redman says "buying drones is not the same thing as building a sovereign, resilient drone industry".

He adds it's "very different" purchasing from overseas manufacturers than "having the ability to produce that capability at scale" in the UK.

Using Ukraine as an example, he says millions of drones are being made and used by the country every year - and the UK is providing about 150,000, external.

"In terms of what we can produce, we are nowhere near that scale. And in a wartime scenario, it's going to be the industry that underpins these uncrewed systems that really wins," he says.

A commander in the Ukrainian army says drones have "dramatically" changed the battlefield since the start of the war against Russia in 2022.

The drone unit commander, who uses the call sign Neo to hide his identity, told Radio 4's Today programme that drones have made it easier for Ukraine "to match Russia" and were its "saviour".

"Technological advantage was the only chance for us. Russia is now in a very bad position and things are getting worse for Russia and a majority of it comes from the drones."

He says drones are a "much cheaper weapon" and more accurate than other missiles.

As we reported earlier, today's defence investment plan will include more than £5bn to be spent on drones over the next four years.

Image source, Reuters

What has happened to the size of the armed forces?published at 09:31 BST

09:31 BST

By Ben Chu

In 1990 - at the end of the Cold War - the army had 153,000 regular soldiers, external in its ranks. This is now down to 73,790, external.

The 2025 Strategic Defence Review recommended, external that the British army's regular force should not drop below 73,000. In its latest update, the Ministry of Defence (MoD) confirmed the number of people applying to enlist in the regular army had fallen by around 40% in 2025 compared to 2024. Since 1990, the number of reservists has fallen from 76,000 to 25,770.

In 1990, the Royal Navy had 48 major combat ships, external (13 destroyers, 35 frigates). That has dropped to seven frigates, external and six destroyers, external. There has been criticism of the Navy's readiness after it took weeks to deploy a single ship - HMS Dragon - to the Gulf to help protect a Royal Air Force base in Cyprus during the Iran war.

In 1990, the RAF had more than 300 combat jets, external - now it has 107 Eurofighter Typhoons, external and at least 37 F-35 Lightning II, externals - which while fewer in number are technically superior.

Uncrewed aircraft systems, also known as drones, now form an element of the UK's military air capabilities which did not exist in 1990.

The threat from drones has been highlighted in the Ukraine conflict where they now kill more people than traditional artillery, external. Analysts say the UK needs to invest considerably more in this military technology.

Image source, Getty Images

The plans that will be released later today contain a "decent transformative element" but "more money is needed" to keep the UK safe, Gen Sir Richard Barrons says.

Speaking to the BBC's Today programme, Barrons - one of the authors of last year's strategic defence review - says: "It is still not going to crack the issue of, in order to defend the UK sufficiently well, sufficiently quickly, more has to be done sooner and that requires more money than is currently on the table."

Barrons, former director of operations for the Army, says the prime minister has warned Russia could attack Nato by 2030. "The plan we're seeing today gets us ready for a fight that might occur in 2030 by not before 2035," he says.

He also says the UK is falling behind its European allies in Nato, who are "spending more money much faster on revitalising and beginning to transform their armed forces".

In terms of capabilities, Barrons says the UK is "pretty much on the bottom - we're not keeping up with our allies, we're certainly not keeping up with our enemies".

"Until we come to terms with the fact that we have to find more money for defence sooner - and yes it will be at the cost of other things we like more - we are simply not going to be ready to defend this country properly," he adds.

There's still bad blood in government over defence funding rowpublished at 08:25 BST

08:25 BST

Henry Zeffman
Chief political correspondent

John Healey resigned as defence secretary almost three weeks ago, meaning that Dan Jarvis will be beside Keir Starmer at the launch of the defence investment plan instead today.

Healey’s resignation was a bitter blow to the prime minister, but Healey’s criticism of the government’s approach was more directly targeted at Rachel Reeves, the chancellor.

There is still a lot of bad blood swilling around government about that.

A source close to the chancellor made the case to me yesterday that Jarvis had managed to get more money for the plan since becoming defence secretary because he had behaved "in a much more collegiate way". The source claimed that "John wasn’t really willing to work with us direct".

An ally of Healey said in response that he had been in regular contact with Treasury ministers until the shortfall in defence spending was identified, at which point No 10 took charge of resolving the issue.

The UK's spending of 2.3% of GDP in 2025 put it just above the mid-point of spending by Nato members, according to figures from the military alliance.

The government has said it will increase it to 2.5% in 2027 with an "ambition" to raise that to 3% in the next Parliament, which is expected to start in 2029 and end in 2034.

It has also committed to increase defence spending to 3.5% of GDP by 2035, in line with Nato commitments.

Former Defence Secretary John Healey - who resigned over the defence investment plan - says the UK needs to be spending 3% on defence by 2030.

He criticised the government for having "no date for reaching 3%, no path to 3.5%".

It is understood that Healey was presented with a plan to take spending from 2.6% of GDP to 2.68% by 2030.

The UK has also committed to a Nato target to spend 5% of GDP on "national security" by 2035.

The government has said this would be made up of 3.5% of GDP on "core defence" and another 1.5% of GDP going on things like protecting critical infrastructure and ensuring civil preparedness.

Image source, EPA/Shutterstock

Dan Jarvis, the new defence secretary, has spent the last two weeks "refocusing" the defence investment plan to ensure it learns the lessons from the wars in Ukraine and Iran, the MoD has said.

This includes how drones have been used to destroy high-value targets, with Jarvis saying the "character of warfare is rapidly changing".

In a brief statement that accompanies the information released by the government ahead of plan's publication, Jarvis says: "In Ukraine and the Middle East, uncrewed systems are defining conflicts.

"This largest ever UK investment into these evolving technologies will help our armed forces stay ahead of our adversaries, backed by the best of our defence industry."

For context: Jarvis took on the role earlier this month after John Healey resigned saying the funding for the defence investment plan fell well short of what is needed. Jarvis has reportedly secured some extra funding - the full plan will be released later.

Today is likely the most significant policy announcement of Starmer's final weekspublished at 07:56 BST

07:56 BST

Henry Zeffman
Chief political correspondent

The defence investment plan is almost certain to be the most significant thing Starmer will announce in his remaining three or so weeks in office.

It was originally meant to be published last autumn in a very different political context, but was delayed repeatedly because of tensions at the top of government about the amount of money available to spend on defence.

It was delayed again a few weeks ago when, just days before the plan was finally about to be published, those same tensions spilled into public view, with John Healey quitting as defence secretary.

He was followed out the door by Al Carns, a junior defence minister. Both argued that the government in general, and Rachel Reeves in particular, were unwilling to fund defence by the amount it needs.

Healey’s resignation is seen by many of Starmer’s closest allies as a pivotal moment on the path to his departure as prime minister, because it undermined Starmer’s ability to make the case that despite difficulties on the domestic front he had done what was necessary to protect the UK from global turmoil.

Image source, Getty Images

Liberal Democrat leader Ed Davey has criticised the defence investment plan as "late and underfunded", which he describes as "unforgivable".

Reacting to information released ahead of its publication, Davey says it represents a "political choice that makes us all less safe, puts jobs at risk and threatens businesses across the country in supply chains".

He says the government has "dangerously short-changed our armed forces" after years of "Conservative negligence".

"Defence chiefs have been forced to make hard choices when they should be given what they need," he adds.