Photo: Chinese Foreign Ministry spokesperson Lin Jian

A Chinese Foreign Ministry spokesperson on Monday urged South Korea to handle the matter of its nuclear-powered submarine cooperation with the US with prudence, with Chinese military affairs experts warning that the move could undermine the non-proliferation treaty.

In response to a question regarding media reports that South Korea and the US will launch the discussions next year on implementing agreements between their leaders on the ROK building nuclear-powered submarines, uranium enrichment and other issues, Chinese Foreign Ministry spokesperson Lin Jian said at a regular press conference on Monday that on the submarine cooperation between the US and the ROK, China has articulated its position more than once.

"We hope South Korea approaches this matter with prudence," Lin said.

Lin's remarks came after South Korea's Yonhap News reported on Sunday that Wi Sung-lac, director of South Korea's Office of National Security, claimed on Saturday that South Korea and the US have agreed to simultaneously conduct consultations in various fields starting next year to implement the agreements reached between the two countries' leaders, including the construction of South Korea's nuclear-powered submarines, uranium enrichment, and reprocessing of spent nuclear fuel. The agreement was reached during high-level discussions held during Wi's visit to Washington DC from Tuesday to Wednesday, according to the report.

During his US visit, Wi met with US Secretary of State Marco Rubio and Energy Secretary Chris Wright, according to the Yonhap report.

Wi claimed that the US and South Korea have agreed to conclude a separate agreement based on Article 91 of the US Atomic Energy Act, which allows the US President to authorize the transfer of military nuclear materials, Yonhap reported, noting that this is similar to the solution Australia is pursuing to acquire nuclear submarines from the US within the AUKUS framework.

Song Zhongping, a Chinese military affairs expert, warned that the South Korea-US nuclear-powered submarine program brings a high risk of nuclear proliferation. He told the Global Times that the US has set a bad precedent with the AUKUS nuclear-powered submarine program with Australia, and now a similar case is emerging for South Korea. The US' indulgence of allowing some of its allies to use its nuclear technologies and nuclear fuel will inevitably undermine the Treaty on the Non-Proliferation of Nuclear Weapons (NPT).

Now that Japan is also hyping its plan to own nuclear-powered submarines, an arms race over nuclear-power submarines could break out, Song said. He noted that the more countries have nuclear-powered submarines, the higher the risk exists of an overflow of nuclear technologies as well as nuclear accidents.

Song further noted that while South Korea is a maritime nation, its coastlines are limited, so it does not really have the need to operate nuclear-powered submarines. 

A nuclear arms race will only undermine peace and stability, Song said.