A senior U.S. official has alleged that China conducted an underground nuclear test on June 22, 2020, at the Lop Nor test site. Assistant Secretary of State Christopher Yeaw cited data from a seismic station in Kazakhstan indicating a magnitude 2.75 explosion, which he said was inconsistent with mining activity or earthquakes.
Yeaw suggested that China may have attempted to conceal the test using “decoupling,” a method that dampens the seismic signature of underground detonations. He emphasized that the blast aligns with what would be expected from a nuclear explosive test.
The Comprehensive Test Ban Treaty Organization (CTBTO) said that the recorded events were too small to confidently determine their cause, while China strongly denied the allegations, calling them “entirely unfounded” and politically motivated. A spokesperson for the Chinese embassy urged the U.S. to uphold international nuclear disarmament commitments.
The allegation comes amid U.S. President Donald Trump’s push for China to join the U.S. and Russia in negotiating a new nuclear arms pact to replace the expired New START treaty. China, which has signed but not ratified the 1996 Comprehensive Nuclear-Test-Ban Treaty, maintains that its nuclear arsenal is significantly smaller than those of the U.S. and Russia.
The Pentagon estimates China currently possesses more than 600 operational nuclear warheads and is expanding its strategic nuclear forces, projecting over 1,000 warheads by 2030.
