Defence Secretary John Healey's resignation letter in full

Defence Secretary John Healey has resigned from Keir Starmer's government.

In a letter to the prime minister, he said the UK's defence investment plan "falls well short of what is required for defence and the country at this dangerous time".

Here is the letter in full:

This is a letter I never expected to write, and I do so now with great regret and reluctance.

I am proud of what we have done in less than two years as a Labour Government. We've stepped up to lead internationally for Ukraine with the Coalition of the Willing and Ukraine Defence Contact Group, established Britain as a leading voice for Europe in NATO, raised defence investment to 2.5% of GDP three years earlier than anyone expected, launched the deepest defence reforms in 50 years, won the biggest UK defence export deals for decades, published a first-of-its-kind Strategic Defence Review, gave our Armed Forces the biggest pay rise in nearly 20 years, boosted military morale, fixed over 1,200 of the worst forces family homes, reset relations with European allies and signed major defence agreements with Germany, Norway and France.

You have led this as PM, earning wide respect at home and abroad. Like me, I know you are exceptionally proud of our Forces and all of those who work in UK Defence.

We came into government, recognising Britain faced a new era of threat which demanded a new era for defence. The SDR (Strategic Defence Review) we jointly commissioned set the 10-year vision to transform our Armed Forces, strengthen alliances, invest in the technology that is changing warfare and back British industry to make defence an engine for growth.

This new era for defence required further investment through the Defence Investment Plan (DIP). The excellent and extensive cross-government work that completed in January-overseen by you, me and the Chancellor - confirmed the scale of the challenge and the rising demands on defence.

Since then, you have been unable, and the Treasury has been unwilling, to commit the resources that the nation needs to defend the country at this time of rising threats.

Since then, the demands on defence have increased still further, as have the UK commitments you have rightly made to allies. Conflict in the Middle East, with the UK now leading the multinational Strait of Hormuz military mission; High North security, with the UK now leading NATO's Arctic Sentry mission; increased Russian activity towards the UK and NATO nations and increased attacks in Ukraine, with the Paris Agreement confirming a British deployment to Ukraine after a ceasefire.

We have worked to secure a Defence Investment Plan that does two things. First, deal with the increasing operational demands on defence now and step up the SDR actions to meet the increasing threat. Second, set a clear path to meet the new NATO commitment you agreed to spend 3.5% of GDP in 2035 through the next Spending Review.

As we have regularly discussed, I am certain that a headmark date for 3% of GDP on defence in 2030 is what Britain must set. This commitment would have strong cross-party support. Other European allies are stepping up in this way.

I know how hard you have worked to get to this point. And in funding the DIP, I fully recognise the strain this places on colleagues in other Departments, both now as you have required spending switched into defence and in the future. I am very grateful to those colleagues who have supported this, and I appreciate how difficult their choices will have been.

As I've outlined to you, there are credible ways of meeting the mid-term funding challenges, working multi-nationally and as other European nations are doing, to allow us to protect our ability to deliver the missions of our Labour Government.

However, your DIP financial settlement - which I was first given in full on Monday afternoon this week-falls well short of what is required for defence and the country at this dangerous time. The extra support is backloaded when the pressure of operations and imperative to speed up readiness to fight is in the first two years and it rises to just 2.68% of GDP in 2030, when we will reach 2.6% next year with the investment we are already making.

You spelled out the threats last week: "it is our intelligence assessment, and the assessment of other countries in NATO, that there could be an attack by Russia on NATO as soon as 2030."

You know what defence needs. You made the argument for this powerfully in your speech at the Munich Security Conference back in February. Without a DIP that meets the moment in this way, I am being forced to make decisions that would reduce the readiness of our Forces and increase the risk to personnel on operations, and could make the country less safe.

After explaining to you that I would not be able to accept a DIP settlement that does not give our Forces the resources they need, I am now left with no other option than to submit my resignation as your Defence Secretary.

I wish you all continuing strength in the exceptional challenges you face as Prime Minister.

As always, our Labour Government will continue to have my fullest support.