UK rearmament and warfighting readiness

On 30 June 2026, the government published its long-awaited Defence Investment Plan (DIP). The government had pledged to publish the DIP before the NATO summit, which begins in Turkey on 7 July 2026.

The DIP has a 10-year focus but specifically sets out the Ministry of Defence’s spending and equipment priorities for the next four years, to financial year 2029/30. Before publishing the plan, the Ministry of Defence (MOD) said that it had been “refocused” towards more immediate priorities, including “getting the latest kit into the hands of military personnel on the frontline”. Concerns over an earlier version of the Defence Investment Plan, and the financial settlement underpinning it, prompted the resignation of Defence Secretary John Healey and Armed Forces Minister Al Carns in early June 2026.

Strengthening warfighting readiness and embracing autonomous and AI technologies underpins much of the plan. However, it also makes significant decisions on the future of existing programmes and capabilities, such as the next-generation fighter aircraft, the Ajax armoured vehicle and the capabilities that will comprise a future hybrid navy.

The MOD has committed to provide an annual update to Parliament on delivery against the DIP. The first annual report will be published in July 2027.

This briefing provides links to Commons research briefings, Committee reports, parliamentary material, UK Government press releases and further reading related to UK rearmament and war fighting readiness.

Defence Investment Plan: Key decisions, 2 July 2026

UK aid: Reducing spending to 0.3% of GNI by 2027/28, 1 July 2026

Estimates Day debate: Spending of the Cabinet Office on security and resilience, 26 June 2026

Conscription and national service in the UK, 24 March 2026

Estimates Day debate: Spending of the Ministry of Defence, 3 March 2026

Strategic Defence Review 2025: Key points and paper series (A high-level overview of the Strategic Defence Review and relevant Commons Library research briefings)

UK defence spending, 10 October 2025

UK defence personnel statistics, 30 June 2025

Defence Committee’s response to the publication of the Defence Investment Plan, 30 June 2026

Evidence to the International Relations and Defence Committee for the inquiry on SDR implementation, 17 June 2026, from (PDF):

• Rupert Pearce (UK National Armaments Director, Ministry of Defence)
• Lt Gen Anna-Lee Reilly (Director-General, Core Delivery, Defence Equipment and Support, Ministry of Defence)
• Avril Jolliffe (Director-General (International), Ministry of Defence)
• Jim Carter (Director-General, Commercial and Industry, National Armaments Director Group, Ministry of Defence)

Evidence to the International Relations and Defence Committee for the inquiry on SDR implementation, 16 June 2026, from (PDF):

• Air Chief Marshal Sir Richard Knighton (Chief of the Defence Staff, UK Armed Forces)

The UK contribution to European Security (PDF), Sixth Report of Session 2024–26, Defence Committee, HC 520, 19 November 2025 and the Government’s response, 20 January 2026

Ready for War? (PDF), First Report of Session 2023–24, Defence Committee, HC 26, 4 February 2024 and the Government’s response, 25 April 2024

Prime Minister’s Office, PM speech announcing the Defence Investment Plan: 30 June 2026, 30 June 2026

Ministry of Defence, £15 billion new funding boost to transform Armed Forces and keep the UK safe, 30 June 2026

Ministry of Defence, The Defence Investment Plan policy papers, 30 June 2026

Ministry of Defence, UK drone transformation to strengthen Armed Forces backed by more than £5 billion, 29 June 2026

Ministry of Defence, New world-leading lab to be built at secretive UK research site, 29 June 2026

Prime Minister’s Office, Exchange of letters between the Prime Minister and The Rt Hon John Healey MP, 11 June 2026

Ministry of Defence, UK tests defence supply chains under war conditions in major exercise, 29 April 2026

Ministry of Defence, Luke Pollard MP, Minister for Defence Readiness and Industry, Speech for Long War Conference, 25 November 2025

Statements and urgent questions

Defence Investment Plan, HL Deb 1 July 2026, Vol 857 cc1069-1083

Defence funding update, 30 Jun 2026, HCWS165

Defence Investment Plan, HC Deb 30 June 2026, Vol 788 cc793-824

Strategic Defence Review: Funding, HL Deb 16 April 2026, Vol 404-408

Personal statements by John Healey and Al Carns following their resignations from the Ministry of Defence, HC Deb 16 June 2026, Vol 783 cc730-734

Strategic Defence Review: Funding, HC Deb 15 April 2026, Vol 783 cc827-848

Strategic Defence Review, HL Deb 3 June 2025, Vol 846 cc679-672

Strategic Defence Review, HC Deb 2 June 2025, Vol 768 cc51-80

Defence Programmes Developments, HL Deb 25 November 2024, Vol 503-514

Defence Programmes Developments, HC Deb 20 November 2024, Vol 757 cc287-382

Debates

Prime Minister’s questions, HC Deb 1 July 2026, Vol 788 cc897-910

Defence Readiness, HC Deb 20 May 2026, Vol 786 cc560-665

Strategic Defence Review 2025, HL Deb 18 July 2025, Vol 847 cc2115-2180

Strategic Defence Review, HL Deb 9 October 2024, Vol 839 cc219-266GC

Robin Potter, Will the UK’s next prime minister finally have a ‘national conversation’ on defence? Chatham House, 3 July 2026

Navy Lookout, Squaring the circle: the nine decisions that will make or break the Hybrid Navy, 3 July 2026

Jonathan Moynihan, What do the former ministers who resigned over the Defence Investment Plan think about it? Forces News, 1 July 2026

James Wharton, Campaigner disappointed as work on 14,000 sub-standard military homes delayed, Forces News, 1 July 2026

Navy Lookout, What the Defence Investment Plan means for the Royal Navy, 1 July 2026

Douglas Barrie, UK Defence Investment Plan: mixed messages, IISS Military Balance Blog, 1 July 2026

Dr Linus Terhorst, Private Capital in UK Defence, RUSI, 1 July 2026

Bee Boileau and Max Warner, Initial response to the Defence Investment Plan, Institute for Fiscal Studies, 30 June 2026

Frank Gardner, Key points from government's defence spending plan, BBC News, 30 June 2026

Sian Grzeszczyk Melbourne, The Defence Investment Plan: What's in, what's out and what it means for the Armed Forces, Forces News, 30 June 2026

Politico, 5 things to know about the UK’s new defense spending plan, 30 June 2026

Navy Lookout, All in on the hybrid navy – the Royal Navy’s surface fleet gamble, 29 June 2026

RUSI, Chief of the Defence Staff's Closing Keynote at Land Warfare Conference 2026 (Video), 24 June 2026

RUSI, Secretary of State Dan Jarvis’ Closing Keynote at RUSI Land Warfare Conference (Video), 23 June 2026

BBC News, Defence Secretary John Healey and Armed Forces Minister Al Carns resignation letters in full, 11 June 2026

Andrew Fox, What the Defence Investment Plan should contain (PDF), Henry Jackson Society, June 2026

Larisa Brown, Is the UK ready for war? The cost of the nation’s defence crisis, The Times (subscription required), 17 April 2026

Sir Bernard Jenkin, Derek Twigg, Chris Donelly, Understanding the UK’s Transition to Warfighting Readiness, Civitas, January 2026

Dr Chris Lewis, Challenges and Opportunities of the Transition to War, RUSI, 8 September 2025

Two of the authors of the Strategic Defence Review (SDR), Lord Robertson and General Sir Richard Barrons, will give evidence to the Defence Committee on the newly published Defence Investment Plan (DIP) on Tuesday 7 July 2026.

National Audit Office, Affordability of the MoD’s investment plan, Scheduled: Autumn 2026