LONDON — Britain will host the headquarters of government and industrial organizations for the trinational Global Combat Air Program (GCAP), according to a treaty signed Dec. 14 with Italy and Japan outlining the project’s management structure.

While the British will provide the headquarters, the treaty arrangement, signed in Tokyo by defense ministers for the three nations, will initially see a Japanese CEO head the governments’ GCAP organization and an Italian CEO leading a parallel industrial headquarters.

The signing of the convention on the establishment of the GCAP International Government Organisation (GIGO) is a crucial step forward in delivering on the three-nation plan to field a sixth-generation combat jet by 2035.

For the British it will also be seen as an important move towards strengthening London’s ties in the Indo-Pacific region following Prime Minister Rishi Sunak’s signing of the Hiroshima Accord with his Japanese counterpart in May.

That pact involves boosting military and industry links between the two nations.

In a statement, British Defence Secretary Grant Shapps said the program aims to be “crucial to global security, and we continue to make hugely positive progress toward delivery of the new jets to our respective air forces in 2035.”

He added, “The UK-based headquarters will also see us make important decisions collaboratively and at pace, working with our close partners Italy and Japan.”

The GCAP treaty signing comes almost a year after the three nations formally agreed to partner on the program, bringing together plans for an Anglo-Italian, next-generation combat jet with the Japanese F-X effort.

A joint development phase is scheduled to launch in 2025, said a statement from the British Ministry of Defence.

No details have yet been released on where in the U.K. the government and industrial organizations will be based and exactly who will lead them.

BAE Systems, Leonardo and Mitsubishi Heavy Industries, the program’s lead companies, said in a joint statement talks were underway to firm up the industrial arrangements.

“Discussions on the future joint industrial construct to deliver GCAP are continuing, with representatives from Leonardo, Mitsubishi Heavy Industries and BAE Systems meeting recently in Tokyo” said the statement.

In September the industry partners announced a collaboration agreement to support ongoing discussions on long-term working arrangements and maturity of the concept and capability requirements for the envisioned combat aircraft.

Around 9,000 employee’s and 1,000 suppliers are already involved in the program, the companies said.

It’s possible the ongoing talks could eventually be expanded to include other partners.

Saudi Arabia has been touted as a potential future partner in GCAP, but media reports earlier this year said that such a move would not be welcomed in Tokyo.

Sweden had been involved in early discussions to partner the UK and Italy in a program known in Britain as Tempest, but dropped out earlier this year.

Within the UK, the effort is being led by BAE Systems in close partnership with Rolls-Royce, Leonardo UK and MBDA UK, all of whom have been deeply involved in the British Tempest program.

Andrew Chuter is the United Kingdom correspondent for Defense News.

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