Nikkei Asia report claimed that the effort is part of the Japanese government's Cross-ministerial Strategic Innovation Promotion Program, aimed at enhance so-called long-term resilience to China's economic approach for the valuable minerals,

On whether the project can significantly reduce reliance on Chinese rare earths, Chinese experts said its short-term effect will be limited. An independent rare-earth industry analyst surnamed Wu told the Global Times that even if Japan's deep-sea rare-earth resources enter an initial development phase, they are likely to meet only a small share of domestic demand, carrying symbolic security value and serving mainly as "strategic insurance" and risk hedging, rather than functioning as a cost- and scale-competitive alternative to China's onshore rare-earth supply system, he said.

Lin Boqiang, director of the China Center for Energy Economics Research at Xiamen University, told the Global Times that rare-earth resources are widely distributed globally, but the real bottleneck lies in refining and processing, where core technologies and the integrated industrial chain remain largely concentrated in China. Even if resources are available, building a complete alternative supply chain would take many years, making it difficult to reduce reliance on China in the short term.

From a global supply-and-demand perspective, experts said, the project is better viewed as a variable to be monitored over time rather than a structural shift.

The JAMSTEC research ship Chikyu departed Shimizu Port in central Japan on January 12 and reached a trial mining site in Japan's exclusive economic zone near Minamitorishima on January 17. Operations began on Friday, with the first rare-earth slurry successfully pumped out early Sunday, according to Nikkei Asia.

Analyst Wu told the Global Times that Japan's achievement in lifting rare-earth slurry from depths of around 6,000 meters near Minamitorishima mainly represents a verification of engineering capability and technical pathways. However, Wu noted that achieving long-term, continuous operations at a scale of hundreds of tons per day — while ensuring equipment durability, maintenance efficiency and controllable ecological impacts — will require multiple rounds of further engineering iteration, he said. At this stage, the breakthrough is better understood as a form of technological reserve and strategic demonstration rather than an immediately scalable supply solution.

Previous surveys near Minamitorishima have identified at least six rare-earth elements at high concentrations contained in seabed mud, Nikkei Asia reported.

Scientists will analyze the composition of the slurry, as well as data obtained from subsea monitoring devices, at research facilities after the ship returns to port in the next two weeks. Attempts will also be made to see if rare-earth elements can actually be refined from it. Following the mission's trial extraction, a large-scale one is planned in the Minamitorishima area in February 2027 to extract about 350 metric tons of mud per day, with the aim of examining the full process through to the separation and processing of rare earths, Nikkei Asia reported.

Wu noted that from an economic perspective, 6,000-meter-deep sea operations are extremely costly. Compared with the cost advantages of China's onshore rare-earth mining and initial processing, Japan's deep-sea rare earths, even if of higher grade, are unlikely to be price-competitive in the short term.

Lin added that economic viability is one of the major constraints. While national security concerns may outweigh costs initially, projects with persistently high expenses will struggle to achieve commercialization. The challenge, he said, is not resource availability, but the time and cost required to establish a competitive, integrated rare-earth industry chain.

Wu added that resource development around Minamitorishima could also face geopolitical and environmental constraints. He noted that deep-sea ecosystems at depths of 6,000 meters remain highly fragile. As international environmental standards for deep-sea mining continue to tighten, such projects may face growing regulatory and compliance pressures in the future, he said.

Previously, China's Ministry of Commerce (MOFCOM) has responded to questions on China's rare-earth export controls to Japan.

"As a responsible major country, China has consistently and actively fulfilled its international non-proliferation obligations. In accordance with laws and regulations, it has imposed controls on all dual-use items, prohibiting exports to Japan for military end-users, military purposes, or any end-use that contributes to enhancing Japan's military capabilities. The aim is to curb re-militarization and nuclear ambitions, and the measures are fully justified, reasonable and lawful," He Yongqian, a spokesperson for the MOFCOM, said on January 22, in response to media questions regarding whether the reportedly measures - Japanese company importing the rare earth from China was asked to submit extra documents which shows overall pictures of the supply chain - were instructed by MOFCOM, and regarding export controls on dual use items what specific measures are being instructed to Chinese exporters.

These measures, aimed at preventing militarization and nuclear ambitions, are fully justified, reasonable and lawful. At the same time, China remains committed to safeguarding the stability and security of global industrial and supply chains, with export control application and review procedures conducted strictly in line with the law, according to He, adding that in this regard, MOFCOM reiterates that export applications meeting the requirements—such as ensuring civilian end use—will be approved.