Britain's Defense Minister Grant Shapps (right), Italy's Defense Minister Guido Crosetto (left) and Japanese Defense Minister Minoru Kihara (center) attend a signing ceremony for Global Combat Air Programme (GCAP) in Tokyo, Japan, on Dec 14, 2023. (PHOTO / AP)

LONDON/TOKYO - Britain, Japan and Italy have signed an international treaty to establish a program aimed at developing an advanced fighter jet, the defense ministers announced on Thursday.

The agreement, which Reuters reported this month, comes a year after the three countries established their first major defense industry collaboration by merging the separate next-generation fighter efforts of London and Tokyo.

The parliaments of each country must ratify the agreement, which aims to see the combat aircraft in flight by 2035. The joint development phase of the program will begin in 2025.

Both the joint government headquarters of the Global Combat Air Programme (GCAP) and its industry counterpart will be based in Britain. The government organization's first chief executive will come from Japan, while the first leader of the business organization will be from Italy, according to the announcement.

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"No nation can do this alone to this level of expertise combined with our skills and our equipment, with our design and ability on production lines," British defense minister Grant Shapps said.

Britain's Defense Minister Grant Shapps (right), Italy's Defense Minister Guido Crosetto (left) and Japanese Defense Minister Minoru Kihara (center) shake hands prior a trilateral meeting in Tokyo, Japan, on Dec 14, 2023. (PHOTO / AP)

"As we face the most complex security environment since World War Two... securing aerial superiority continues to be a crucial challenge that we must achieve," Japan's defense minister, Minoru Kihara, added, flanked by Shapps and Italian Defense Minister Guido Crosetto in Tokyo.

Kihara did not say who would head the company, but said that he would ensure "the best person for the job" is selected.

The supersonic stealth jet will feature a radar that can provide 10,000 times more data than current systems, the British government has said.

Britain's BAE Systems, Italy's Leonardo, European missile maker MBDA and engine maker Rolls-Royce are involved in the project.

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Reuters has reported that Japan's Mitsubishi Heavy Industries, Japanese avionics manufacturer Mitsubishi Electric Corp, and engine makers IHI Corp and Avio Aero are also involved.