Japanese Prime Minister Fumio Kishida and South Korean President Yoon Suk Yeol will announce the framework on Nov. 17 in the United States, where they are expected to join the Asia-Pacific Economic Cooperation (APEC) meeting, the paper said.
Japan and South Korea, both highly dependent on energy imports, plan to work together to negotiate prices and volumes, Nikkei said, and state-backed financial institutions would help companies to raise funds for hydrogen and ammonia projects outside Japan and South Korea.
No comment was immediately available from Japan's trade ministry.
Japan's Kishida visited the Middle East in July to promote cooperation in green and renewable energy, including hydrogen and ammonia supplies, which Japan wants to play a greater role in its energy mix to cut fossil fuel use.