The US bill requires the US to coordinate Japan's role in the AUKUS program with the UK and Australia

A bipartisan group of senior US senators introduced a bill on Wednesday that would require officials involved in the AUKUS defense program with the United Kingdom and Australia to engage with them and Japan on how to include Japan in the program.

The bill, introduced by Republicans Mitt Romney, Bill Haggerty and Jim Risch, and Democrat Tim Kaine, would have the United States coordinate a path to Japan's cooperation in advanced technology programs as part of the second pillar of AUKUS.

AUKUS was formed in 2021 to counter the rise of China. Its first pillar involves cooperation between the three partners to supply Australia with nuclear-powered submarines, but other countries have raised the possibility of joining the second pillar to develop other high-tech weapons.

The partners announced in April that they plan to work with Japan on specific Pillar 2 projects and hold discussions this year.

Announcing the AUKUS Engagement Coordination Act with Japan, in a statement from his office provided to Reuters, Mr. Romney said, “America must work with its allies to counter China's growing aggression.

“This legislation would require coordinators of the US Department of State and Defense (AUKUS) to engage with the Japanese government and consult with their counterparts in the United Kingdom and Australia to discuss … certain advanced technical cooperation activities under AUKUS,” the statement said.

According to Kaine, AUKUS is “essential to keeping the Indo-Pacific free and open” and the bill will help “chart a path to include Japan in AUKUS and expand defense industrial cooperation among America's allies.”

A member of the Senate Foreign Affairs Committee, Mr. Risch said the bill would require the Biden administration to express Japan's interest in joining AUKUS to assess the unique technological contributions Tokyo can make and validate its export control system. Adequately integrated with existing partners.

“Importantly, it also ensures that the executive consults with its counterparts in the UK and Australia before expanding AUKUS,” he added.

AUKUS already faces obstacles stemming from strict U.S. restrictions on technology sharing, and Japan's involvement has prompted some reluctance, with officials and experts highlighting the country's vulnerabilities in technology sharing and information security. (Reporting by David Brunstrom; Editing by Chisu Nomiyama)