TOKYO — Japanese Prime Minister Sanae Takaichi has expressed interest in cooperating with the U.S. on developing rare-earth minerals off the coast of Japan, an issue that might make the agenda at her mid-March bilateral summit as the allies try to build a supply chain not overly dependent on China.
“I would like to speed up this project with the full participation of the U.S.,” Takaichi said Feb. 8 of a Cabinet Office-led project that successfully test-drilled deep-sea mud believed to contain rare earths, speaking on a Nippon Broadcasting System program.
The Japan Agency for Marine-Earth Science and Technology’s Chikyu research vessel returned to the Port of Shimizu in the central Japanese city of Shizuoka on Saturday after test drilling off the coast of Minamitorishima, an island roughly 2,000 kilometers southeast of Tokyo.
Shoichi Ishii, program director of the Cabinet Office-led project, the Cross-ministerial Strategic Innovation Promotion Program, said Saturday that researchers “succeeded in continuously pumping rare-earth mud from a depth of 5,569 meters, a world first.”
Mud in the seabed off the island’s coast is believed to contain high concentrations of such key rare-earth elements as dysprosium and gadolinium, which have applications in high-performance magnets for electric vehicles and in nuclear reactor control rods.
Collected mud and other materials will be studied in detail at domestic facilities, with results due out in 2026. The Cabinet Office aims to quickly commercialize the project as a first step toward exploiting domestic seabed resources.
Takaichi intends to position the Minamitorishima mining project as an area of cooperation under the “Japan-United States Framework for Securing the Supply of Critical Minerals and Rare Earths Through Mining and Processing,” which she and U.S. President Donald Trump signed this past October on his visit to Japan.
Japan has strengths in such processing technologies as refining but has not been able to produce rare-earth minerals domestically. Commercializing rare earths mined off the Minamitorishima coast poses challenges, including mass production and transportation. Takaichi sees room for cooperation with the U.S.
Takaichi is scheduled to meet with Trump at the White House on March 19. Strengthening economic security cooperation will be a major theme there as China uses export restrictions on critical minerals and rare earths as a diplomatic bargaining chip — a shared concern for both Japan and the U.S.
China accounts for roughly 70% of global rare-earth mine production. As of 2024, Japan was sourcing 63% of its supplies from China.
Sino-Japanese relations have deteriorated recently, with China restricting exports of rare-earth-related products to Japan. In November 2025, Takaichi had told Japanese legislators that a hypothetical Taiwan contingency could be a “survival-threatening situation” for Japan, possibly necessitating an armed response by Japan to aid the U.S.
The U.S. and China are at odds over Trump’s tariffs and Beijing’s restrictions on rare-earth exports, with the deadline for negotiations continuing to be postponed. The U.S. is also seeking cooperation with like-minded countries to reduce its dependence on China for rare earths.
At a ministerial-level meeting in Washington on Feb. 4, the U.S., Japan and the European Union, discussed reducing reliance on imports of rare earths and other Chinese products.