Japan is accelerating a decade-old plan to extract rare earths from the deep seabed, an ambitious initiative given extra impetus by the country¡¯s drive to cut reliance on Chinese supply.

A state-owned vessel is scheduled to return to port this month after fitting equipment below the surface of Japanese waters, near a coral atoll 2,000 kilometers from Tokyo. The aim is to pull metal-bearing mud from the seabed for tests as early as February 2027, according to the government body running the project.

¡°It¡¯s about economic security,¡± said Shoichi Ishii, program director for Japan¡¯s National Platform for Innovative Ocean Developments. ¡°The country needs to secure a supply chain of rare earths. However expensive they may be, the industry needs them.¡±

Rare earths ¡ª a set of metallic elements used in smartphones, electric vehicles and fighter jets ¡ª have become a political flash point, with China using its dominance of the global supply chain as a crucial bargaining chip in last year¡¯s trade war with the U.S. More recently, Beijing banned exports to Japan of products destined for use in military applications, marking an escalation of a diplomatic spat between the countries.

This is an issue for Japan. Despite spending heavily on securing alternative supplies ¡ª from investing in a separation facility in France to long-term financial backing for Australian miner Lynas Rare Earths ¡ª the country still imports roughly 70% of its rare earths from China.

Mining the seabed will not solve this problem any time soon. Even if tests were to reveal a promising resource, cost and logistics would present major challenges to any potential developer. Large-scale commercial mining of metals from the seabed has never been achieved, despite widespread exploration.

The U.S. ¡ª which hasn¡¯t ratified a United Nations treaty that regulates deep-seabed mining in international waters ¡ª has moved to accelerate the approval process after President Donald Trump last year signed an executive order ¡°unleashing America¡¯s Offshore Critical Minerals and Resources.¡± But the latest changes are likely to raise concerns globally, with the International Seabed Authority now finalizing its own rules governing environmental safeguards.

Japan¡¯s project, however, lies within its own territorial waters ¡ª near Minamitori Island, which marks the country¡¯s easternmost point. According to the Cabinet Office, the cross-ministerial body responsible for deep-sea mining, around 350 tons per day of mud will be brought to the surface from a depth of between 5 and 6 kilometers.

This will be tested to see which rare earths are present and in what quantities, said Tadanori Sasaki, a senior research director at the Institute of Energy Economics. What happens next will depend on these results.

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