Russia confirms rare nuclear supplies shipment to China, US alarmed

Meanwhile, concerns about U.S. security have been expressed as a result of this cooperation between China and Russia, and the U.S. government has urged the Biden administration to "stop Rosatom and the PRC's dangerous cooperation."

Since September, three batches of fuel from TVEL have been shipped by rail to the Chinese factory, with the most recent shipment being highly enriched uranium, World Nuclear News reported in January. 

A little bit more than 30% of the uranium contains uranium-235, which makes up less than 1% of uranium that occurs naturally. 

Nuclear weapons typically contain about 90% uranium-235 and plutonium, while fast reactors need a concentration of uranium-235 of about 20%. 

The danger of using highly enriched uranium in China's reactors is that it might cause China to increase the size of its nuclear arsenal, as per experts. 

The development of a closed nuclear fuel cycle in China, which reprocesses the leftover uranium and plutonium isotopes in spent fuel, is a component of the country's strategy to reduce the danger of shortages.

A direct threat to U.S. security?

Rosatom and China's Atomic Energy Authority signed a comprehensive long-term cooperation agreement on the construction of fast-neutron reactors and closed nuclear fuel cycles during the March visit of Chinese President Xi Jinping to Russia.

The safety of China's fast reactors has, however, prompted several specialists to express their concerns. 

Reactors employ liquid sodium as the reactor coolant, Tian Li, vice president of the nuclear power branch of the China Electric Power Promotion Council, warned that it "easily catches fire both in air and in water, and it can leak easily."

The Chinese foreign ministry has previously asserted that China and Russia engage in "normal civilian nuclear cooperation within the framework of international obligations."

America's disagreements with China and Russia's nuclear energy cooperation is that it sees it as a direct threat to U.S. security, noted the SCMP report. 

"China and Russia have placed nuclear weapons, space warfare, and long-range strike at the center of their strategies to counter the United States and its allies and partners," the U.S. Department of Defense stated in March.

Meanwhile, China has repeatedly maintained that its intention is to create a closed nuclear fuel cycle, more focused on lowering the possibility of shortages than on creating nuclear weapons.