Deep-sea showdown: China blasts U.S. stockpiling plan amid rare earth supply fight

Why is China challenging the U.S. deep-sea metals stockpile strategy?

China‘s foreign ministry has called on the United States to respect international legal frameworks regarding seabed mining, following reports that the Trump administration is drafting an executive order to enable stockpiling of deep-sea metals. These metals, crucial for electric vehicle batteries, renewable energy technologies, and advanced weapon systems, are viewed as strategic resources in the global economic competition for critical minerals.

According to a report in the Financial Times, the U.S. executive order would aim to strengthen domestic reserves of battery-related metals such as nickel, cobalt, manganese, and rare earth elements, many of which are found in polymetallic nodules located in the Clarion-Clipperton Zone of the Pacific Ocean. The reported U.S. move is part of a broader effort to reduce reliance on China, which currently dominates the global rare earth supply chain, from mining and refining to magnet production.

China’s foreign ministry spokesperson stated on Monday that “no country should circumvent international law for seabed resource exploration,” adding that deep-sea mineral resources are the “common heritage of mankind.” These comments follow mounting geopolitical and industrial tensions between the world’s two largest economies, which have increasingly extended beyond trade into technology, climate policy, and critical infrastructure.

What legal frameworks govern deep-sea mining?

The core of China’s objection lies in the U.S.’s refusal to ratify the United Nations Convention on the Law of the Sea (UNCLOS), the international treaty that provides the legal basis for ocean governance, including seabed exploration outside national jurisdictions. Under UNCLOS, the International Seabed Authority (ISA) is responsible for regulating mineral-related activities in international seabed areas, issuing exploration contracts and ensuring environmental protections.

While China is a signatory to UNCLOS and holds multiple exploration contracts granted by the ISA, the United States has not ratified the treaty despite decades of bipartisan debate. This non-ratification weakens the U.S. position in formally accessing seabed mining rights through the ISA, raising questions about the legal viability and global legitimacy of any unilaterally enacted executive order.

Industry experts suggest that any effort by the United States to stockpile metals extracted through non-ISA-authorised means could trigger diplomatic disputes and environmental backlash, especially from Pacific Island nations and environmental groups concerned about the ecological risks of deep-sea mining.

What’s driving U.S. interest in deep-sea minerals?

The potential executive order is part of a larger strategy by the U.S. to decouple from Chinese-controlled supply chains for materials essential to national security and clean energy goals. As the U.S. aims to electrify its vehicle fleet and expand domestic manufacturing of solar panels and wind turbines, the Biden and Trump administrations have both prioritized the diversification of mineral sources.

Efforts to secure non-Chinese supply chains have included the formation of the Minerals Security Partnership with countries such as Australia, Canada, Japan, and the United Kingdom. However, the deep seabed remains largely untapped and presents one of the few remaining frontiers for mineral exploration—particularly in light of limited terrestrial alternatives.

According to the U.S. Geological Survey, China currently processes over 85% of the world’s rare earth elements. The concern is not only about mining but refining capacity—an area where China holds a near-monopoly. The U.S. has historically been dependent on Chinese rare earths since the closure of its major Mountain Pass mine in the early 2000s, although that site has since resumed production.

How does China dominate the rare earth supply chain?

China’s advantage in rare earths and other critical minerals has been built over decades through strategic investments in mining, refining, and technological processing. Chinese companies are deeply integrated into global supply chains and maintain partnerships in Africa, Southeast Asia, and South America, securing access to cobalt, lithium, and other essential materials.

In addition to ISA exploration contracts in the Pacific Ocean, Chinese state-backed firms like China Minmetals and China Ocean Mineral Resources Research and Development Association (COMRA) have significant seabed exploration programs underway. These organisations operate with strong government support and are closely aligned with China’s Belt and Road Initiative and long-term strategic planning around green technologies and resource security.

This context has raised concerns in Washington about supply vulnerability, especially given recent incidents in which China imposed export restrictions on rare earths and other critical minerals in response to geopolitical conflicts.

What environmental and political concerns surround seabed mining?

Even as nations race to secure critical minerals, deep-sea mining remains highly controversial. The Clarion-Clipperton Zone, stretching between Hawaii and Mexico, is believed to contain billions of tonnes of polymetallic nodules that could yield nickel, cobalt, and rare earths. However, scientists warn that disturbing these habitats could result in irreversible damage to ecosystems that are not yet fully understood.

Environmental organisations such as Greenpeace and the Deep Sea Conservation Coalition have called for a moratorium on commercial seabed mining until more research is conducted. In 2021, the Pacific Island nation of Nauru triggered a clause in UNCLOS demanding that the ISA fast-track regulations within two years—a timeline that expired in July 2023, prompting further debate about how soon commercial mining might proceed.

The ISA has since delayed decisions on issuing exploitation licenses, citing the need for more comprehensive environmental frameworks. Meanwhile, countries like Norway have moved forward with their own seabed mineral exploration programs within national jurisdictions, a development that could serve as a model for others.

Could U.S. action worsen global tensions over mineral security?

Analysts warn that a unilateral U.S. move to begin stockpiling seabed metals without international oversight could escalate tensions in already fragile diplomatic relationships, especially in the Indo-Pacific region. Small island nations—many of whom rely on marine resources for food and income—have voiced concern that external powers may exploit the seabed without their consent or participation.

Moreover, any executive action bypassing the ISA could open a legal grey area that encourages similar actions by other non-UNCLOS states, undermining multilateral governance and eroding trust in international institutions. This risk could weaken global cooperation on climate goals, which depend on stable access to minerals for decarbonisation technologies.

Expert opinion from international legal scholars suggests that while the U.S. has legitimate national security interests in securing mineral supply chains, a path that avoids multilateral engagement may ultimately prove short-sighted. By contrast, building partnerships for ISA-backed exploration or supporting the development of ethical, sustainable terrestrial mining may provide a more globally accepted route.

What lies ahead for seabed governance and critical minerals?

As demand for energy transition minerals rises, competition over new sources—including the deep seabed—is expected to intensify. The situation presents a pivotal moment for the future of international resource governance. With the U.S. pushing to reduce dependence on China, and China defending its influence over rare earth markets, the potential for clashes on legal, environmental, and geopolitical fronts is mounting.

Whether the U.S. decides to proceed with the proposed executive order may set a precedent not just for American mineral policy but for how countries view the global commons. The battle for seabed metals could become a defining test of whether resource security and environmental stewardship can coexist—or whether strategic competition will erode international norms.