UK, Japan and Italy agree to build joint advanced fighter jet

The UK, Japan and Italy have agreed to jointly build one of the world’s most advanced fighter jets by 2035 in their first-ever trilateral military programme aimed at expanding their defence capabilities to address increasing security threats from China and Russia.

The Global Combat Air Programme (GCAP), is being developed at the same time as a rival Franco-German-Spanish project, which has been plagued by political and industrial tensions between the partners.

Under the accord agreed on Friday, the UK and Italy will merge their existing Future Combat Air programme, dubbed Tempest, with Japan’s own F-X project. The three nations will share the development costs, estimated at tens of billions of dollars, although a final decision on the exact contributions will be decided based on a joint assessment of costs and national budgets.

“By working together in a spirit of equal partnership, we are sharing the costs and benefits of this investment in our people and technologies,” the leaders of the three nations said in a joint statement. “Importantly, the programme will support the sovereign capability of all three countries to design, deliver and upgrade cutting-edge combat air capabilities, well into the future.” 

The deal, which required years of negotiation, marks an unprecedented departure for Japan. It has historically worked exclusively with US partners for big military equipment but has sought deeper security ties with a range of allies to prepare for the possibility of a war with China over Taiwan.

The fighter jet is also part of Japan’s growing defence ambitions with Prime Minister Fumio Kishida saying this week that the government plans to set aside ¥43tn ($315bn) for its five-year defence budget, a 57 per cent increase from the previous period.

People with direct knowledge of the discussions said Tokyo’s decision to partner with the UK and Italy was driven by growing concerns in government and industry that its domestic defence sector would be unable to maintain its capability to develop modern military equipment and weapons by depending solely on the US, which tends to keep its cutting-edge technology to itself.

Defence ministry officials said Japan would continue to work closely with the US, stressing that its selection of the UK and Italy as partners was made only because Washington did not have the same timeline for the development of its next fighter jet.

“The United States supports Japan’s security and defence co-operation with like-minded allies and partners,” the US Department of Defense said in a joint statement with Japan’s defence ministry.

Britain’s collaboration with Italy and Japan was on Friday hailed by prime minister Rishi Sunak as evidence that “the security of the Euro-Atlantic and Indo-Pacific regions are indivisible”.

The UK has been seeking to strengthen relations with the Pacific region, most notably with the so-called Aukus initiative that saw London, Washington and Canberra agree to collaborate on nuclear-powered submarine technology.

However, the UK’s foreign policy and defence doctrine — known as the “integrated review” and published in 2021 — is being rewritten by Downing Street to reflect the challenges thrown up by Russia’s invasion of Ukraine.

The original paper was billed as Britain’s “tilt to the Pacific”, but the Ukraine conflict is likely to see the revised paper represent something of a pivot back to Europe. The UK committed £2bn towards the Tempest programme, key to retaining British sovereign combat air skills and jobs once the Eurofighter Typhoon comes out of service, over an initial four-year period.

The new programme will be led by the national defence champions of each country: BAE Systems in the UK, Leonardo of Italy and Japan’s Mitsubishi Heavy Industries. The three companies have already been collaborating on a number of critical areas, including propulsion and radar technologies.

The three countries will now work together to establish the concept for the main fighter — which they said would be equipped with “advanced sensors, cutting-edge weapons and [an] innovative data system” — with the aim of launching the development phase in 2024.

The UK and Japan have both said the door was open for others to join the programme.

It is not yet clear whether Sweden, which has had a minor involvement since 2019, wants to deepen its participation.