Policy paper

UK-Japan Defence Ministerial Meeting 2025: Joint Statement

Published 28 August 2025

The Rt Hon John Healey MP, Secretary of State for Defence of the United Kingdom of Great Britain and Northern Ireland (hereinafter referred to as the “UK”), and H.E. Mr Nakatani Gen, Minister of Defense of Japan, held a Defence Ministerial Meeting on 28 August 2025 in Tokyo.

Responding to an increasingly severe international security environment and sharing the recognition that the security and prosperity of Euro-Atlantic and Indo-Pacific are indivisible, the two Ministers emphasised the UK and Japan’s deep strategic alignment and reaffirmed the Enhanced Global Strategic Partnership. They committed to further strengthening defence capabilities and increasing security cooperation to help safeguard global peace and stability.

The Ministers affirmed that as each other’s closest security partners in Europe and Asia respectively, the UK and Japan would continue to take leadership roles in the international community’s efforts to maintain and strengthen the free and open international order based on the rule of law and to uphold the principles of the United Nations (UN) Charter, including respect for sovereignty and territorial integrity, and the United Nations Convention on the Law of the Sea (UNCLOS).The Ministers reiterated their serious concerns about the situation in the East China Sea as well as the South China Sea and continue to strongly oppose any unilateral attempts to change the status quo by force or coercion.

They reaffirmed the importance of peace and stability in the Taiwan Strait, which is of critical importance to global prosperity, and stressed their strong opposition to unilateral attempts to change the status quo by force or coercion. They called for restraint and the avoidance of any further actions that undermine peace and stability. They also strongly condemned the advancement of North Korea’s nuclear and missile activities, and reaffirmed the commitment towards the goal of complete, verifiable and irreversible dismantlement of all North Korean weapons of mass destruction and ballistic missile programmes.

The Ministers reiterated that President Putin’s illegal, unjustifiable, and unprovoked full-scale invasion of Ukraine threatens the security of the Euro-Atlantic and Indo-Pacific and is a flagrant violation of the UN Charter. They condemned the provision to Russia of dual-use assistance by China and of military assistance by North Korea and Iran. They reiterated the UK and Japan’s unwavering support for Ukraine in defending its freedom, sovereignty, independence and territorial integrity and emphasised the importance of stepping up action against Russia’s war economy and of further support to Ukraine. The UK welcomed Japan’s ongoing support for Ukraine through the NATO Comprehensive Assistance Package (NATO CAP), participation in the multilateral exercise Sea Breeze 2025, and Japan’s willingness to join the NATO Security Assistance and Training for Ukraine (NSATU). The Ministers welcomed the growing ties between Japan and NATO, including through the assistance to Ukraine.

The Ministers welcomed the arrival in Japan of the UK Carrier Strike Group (CSG) during its 2025 Indo-Pacific deployment (Operation HIGHMAST) and recognised CSG’s role in maintaining regional stability and upholding the international order. Op HIGHMAST has directly advanced cooperation between UK and Japanese military capabilities in the air and maritime domains, as shown by multilateral exercises along with US, Australian, Norwegian and Spanish ships. The Ministers welcomed the first landing of UK F-35B aircraft on JS KAGA and reaffirmed the value of Japan Maritime Self-Defense Force (JMSDF), Royal Navy and Royal Air Force interoperability as demonstrated through future Japanese participation in exercises with CSG.

The Ministers welcomed the ongoing use of the Reciprocal Access Agreement (RAA) to enable regular defence cooperation, increasing interoperability and realising an even more ambitious programme of more frequent and complex exercises. Furthermore, the Ministers welcomed the first application of the Japan Self-Defence Forces’ asset protection measure for the UK Armed Forces.

The Ministers acknowledged the depth of the bilateral maritime partnership, including Japan’s support to UK Offshore Patrol Vessels. The Ministers noted that their continued regional presence serves to promote maritime security, enhance cooperation and contribute to the rules-based international order and engagement with international partners.

The Ministers welcomed UK and Japanese collaboration on Women, Peace and Security (WPS) across all services of the Japan Self-Defense Forces and the UK Armed Forces, and look forward to further engagement. As responsible nations, the UK and Japan stand united in building an inclusive and resilient security environment - one in which all individuals, regardless of gender, are empowered to contribute to peace and stability. The Ministers also affirmed their intention to advance cooperation on WPS in the Indo-Pacific, including through joint initiatives, capacity-building efforts, and engagement with regional partners.

The Ministers noted the continuation of our bilateral land exercise, Exercise Vigilant Isles, as a means of enhancing interoperability, and welcomed potential expansion of the exercise to Euro-Atlantic allies and likeminded partners in the near future, beginning with observers this year.

The Ministers reiterated that the cyber and electromagnetic domain is at the heart of modern warfare and underpins our shared defence and security. Under the Japan-UK Cyber Partnership, they appreciated the substantial progress in bilateral cyber cooperation and the effort to develop a joint roadmap of cyber activity. They highlighted the value of joint exercises, including Defence Cyber Marvel, to enable the sharing of best practice between the UK Armed Forces and Japan Self-Defense Forces. The Ministers looked forward to deepening cooperation between the UK’s Cyber & Electromagnetic Directorate and JSDF Cyber Defense Command.

The Ministers acknowledged the strengthening relationship between the Royal Air Force (RAF) and Japan Air Self-Defense Force (JASDF), as demonstrated by their joint efforts during Operation HIGHMAST and interoperability efforts in preparation for the Global Combat Air Programme (GCAP). The Ministers welcomed the future deployment to Europe, including the UK, by Japanese fighter aircraft and supporting transport aircraft.

Recognising the significance of the GCAP, the Ministers reaffirmed their personal commitment to it and to accelerating work to conclude the first international contract between the GCAP International Government Organisation (GIGO) and industry joint venture, Edgewing, by the end of 2025. This will be the first contract to set both entities to work together to support capable, affordable and timely programme delivery by 2035. The Ministers noted the broader benefits from our countries’ respective combat air sectors in driving growth and productivity, sustaining high-skilled jobs, and acting as catalysts for investment in research and development. The Ministers reaffirmed the importance of sustaining respective national aerospace sectors and maximizing emerging technologies to meet the future threat and protect those critical industries.

The Ministers recognised the critical importance of space capabilities and the essential services they provide to our collective security, prosperity and daily lives.  As responsible spacefaring nations, and acknowledging the increasing contested and congested nature of the space domain, the UK and Japan remain steadfast in their commitment to the Outer Space Treaty and the peaceful uses of outer space, ensuring space remains a safe, stable, secure and sustainable environment for future generations. The Ministers highlighted the significant opportunities for further alignment and harmonisation of our efforts in this critical domain. They expressed their enthusiasm for deepening space cooperation, through both defence engagements and industrial collaboration. The Ministers affirmed their willingness to advance cooperation in the space domain through exchange of opinions on satellite communications and Space Domain Awareness between each force.

The Ministers reaffirmed their enduring commitment to enhancing UK-Japan industrial and technology collaboration through the High-Level Steering Panel on defence capability. The Ministers welcomed the Panel’s October 2024 Letter of Intent for Maritime Defence Equipment and Technology Cooperation. The Ministers welcomed subsequent cooperation on Future Ship Technology and Maritime Industrial Cooperation, including delivery of the UK-Japan Integrated Power and Energy Systems symposium and the Japan-UK Defence Industry Dialogue for Defence Industry Innovation Forum at DSEI Japan in May 2025.

The Ministers reiterated the Royal Navy and Japan Maritime Self-Defense Force’s interest in exploring maritime advanced capability cooperation. The Ministers welcomed Japan’s recent participation in Exercise TALISMAN SABRE 25, where the AUKUS nations worked alongside Japan to strengthen cooperation on the defence use of maritime autonomous systems.

The Ministers looked forward to continuing substantive discussions at the sixth UK-Japan Foreign and Defence Ministers’ Meeting (“2+2”) in 2026 in the UK.