Expect more joint South China Sea patrols, US says ahead of summits with allies

Sullivan also said Washington and its existing Australian and British partners in the AUKUS security pact would explore possible Japanese involvement in Pillar II of the project, something the Biden-Kishida summit would address.

“We’re prepared to work with additional partners beyond the three of us, where they can bring capabilities, and Japan is one of the countries that could very well bring capabilities to that,” Sullivan said.

“Japan could be a critical contributor,” he said. “You will see when they speak tomorrow, an indication that that’s the direction we’re moving in.”

Sullivan said Biden and Kishida would announce measures to enhance defence and security cooperation, and in space exploration.

The US ambassador to Japan said earlier on Tuesday the US would have a “fundamentally” changed command posture for its forces in Japan to allow for better coordination, with a new military headquarters Japan plans to unveil next year, moves that would boost deterrence in the face of Chinese pressure.