The United States has shared newly declassified information about a suspected underground nuclear explosion conducted by China in June 2020 at the Lop Nur test site. Christopher Yeaw, Assistant Secretary of State for Arms Control, presented the findings at the Conference on Disarmament in Geneva, urging China and Russia to engage more actively in nuclear disarmament efforts.

According to US officials, seismic data indicated a probable nuclear explosion, raising concerns about China’s rapidly expanding nuclear arsenal and lack of transparency. The US warned that China could reach nuclear parity with other major powers within the next few years.

China strongly rejected the allegations, calling them baseless and accusing the US of attempting to justify its own potential nuclear testing. The dispute comes amid heightened global tensions following the expiration of the New START treaty, which had limited nuclear arsenals between the US and Russia.

Experts warn that growing distrust and lack of arms control agreements could trigger a new global nuclear arms race, increasing risks to international security.