China has likely resumed producing weapons-grade uranium after a pause that analysts trace to 1987, according to a Nov. 2 analysis by nuclear researcher Hui Zhang. At Emeishan in southwestern China, satellite images show a fourth enrichment plant that appeared complete in April. Zhang’s case for a military role draws on 16 years of fuel records and estimates. By his accounting, China’s other plants and its imports could have supplied all the enriched uranium its power reactors needed over that period.

Whether China needs fresh uranium for weapons is a point of disagreement among nuclear researchers. The Federation of American Scientists estimates that Beijing has about 620 warheads today. Zhang calculates that China’s older uranium stock could support roughly 670 in total. The federation’s researchers think existing stocks might support close to 1,000.

What satellite images reveal about weapons-grade uranium

The state-owned China National Nuclear Corp. operates the Emeishan complex in Sichuan province. Its third enrichment plant began operating in 2023, according to Zhang, a researcher at Harvard University’s Belfer Center. An April 25 satellite image showed that construction of a fourth plant appeared finished. If the fourth plant starts operating by year’s end, Zhang estimates Emeishan will have about 2.5 times its 2022 enrichment capacity.

Zhang believes some of the capacity already in service likely supplies the weapons program. He does not claim the newest plant has begun producing weapons-grade uranium. Most power reactors use fuel containing only a few percent uranium-235, while weapons-grade uranium generally contains at least 90%. A photograph of the building cannot distinguish between them.

Why China’s reactor fuel figures matter

China has a clear civilian reason to expand enrichment. As of September, it had 64 power reactors operating and another 38 under construction. The question is how much of that demand falls to Emeishan.

Zhang examined fuel imports, exports and estimated output at China’s two other major enrichment sites, Lanzhou and Hanzhong. From 2010 through 2025, he found, those two sites and imports could have covered the civilian fleet’s needs, even after exports. That leaves room for military production at Emeishan without creating an obvious shortage of civilian fuel.

The outlook through 2035 is less certain. Zhang’s projection assumes China keeps adding capacity at Lanzhou or Hanzhong and continues importing enriched uranium at recent levels. A government expecting to rely less on foreign suppliers would have a civilian reason to build ahead of demand. Surplus capacity alone cannot establish where the uranium goes.

How much weapons-grade uranium does China need?

In its July assessment of China’s nuclear arsenal, the Federation of American Scientists concluded that existing uranium and plutonium inventories might support about 1,000 warheads by the turn of the decade. Its researchers identified two unknowns: which warhead designs China will build and how much material each requires. Zhang’s lower figure reflects his estimate of the uranium available and the average amount each weapon would use.

The Pentagon projects that China will have more than 1,000 warheads by 2030. Under Zhang’s estimate, Beijing would need new weapons-grade uranium well before reaching that number. Under the federation’s assessment, it might approach that number using older stocks. Both estimates concern what China couldbuild. Neither measures what Emeishan has produced.

What Beijing has disclosed

In an April report on its nuclear treaty commitments, China said it had offered 30 facilities for International Atomic Energy Agency safeguards, including a uranium enrichment plant. Zhang says Beijing has never offered any of the Emeishan plants. China participates under a voluntary safeguards agreement, so the site’s absence limits independent verification without itself establishing a treaty violation.

Washington is also expanding the infrastructure behind its arsenal. As USA Herald reported, the Energy Department approved construction of a South Carolina facility to make plutonium pits for U.S. nuclear warheads. The U.S. decision identifies the product and its intended use. Beijing has disclosed neither at Emeishan. Zhang has called on China to say what the plant is for and publish its enrichment capacity.