The United States and Japan have reached an understanding on their respective roles in a potential joint nuclear power project involving Westinghouse Electric Company and Japanese nuclear equipment makers, Dan Lipman, president of global business initiatives at Westinghouse, told Reuters on Saturday.

The project is expected to be part of a second round of deals under Japan’s $550 billion investment package, sources said, with momentum growing globally as nations aim to expand domestic energy resources and reduce vulnerability to supply shocks.

Speaking at the Indo-Pacific Energy Security Ministerial and Business Forum in Tokyo, Lipman emphasized that the agreement includes clear responsibilities for both governments, including the supply chain within Japan. “These are very strategic projects that are critical to Westinghouse and our Japanese partners. We’re continuing to work on the transactions until projects are identified and ready for deployment,” he said, adding that further details are yet to be finalized.

Westinghouse, jointly owned by Cameco and Brookfield, is planning investments of up to $100 billion in pressurized water reactors and small modular reactors. Japanese companies such as Mitsubishi Heavy Industries, Toshiba, and IHI Corporation are expected to play key roles in the project, according to Westinghouse.

“They are critical partners for us, and they’ll have an important role,” Lipman said, without providing further specifics.

Separately, U.S. power equipment maker GE Vernova and Hitachi announced a joint initiative to explore projects using their BWRX-300 small modular reactors in Southeast Asia, signaling growing interest in modular nuclear technology for the region.

The collaboration reflects both countries’ push to strengthen nuclear energy capabilities and diversify energy sources amid global supply uncertainties.