US Accuses China of Conducting Secretive Nuclear Arms Tests

A U.S. diplomat said one nuclear test occurred in June 2020. He further accused China of taking measures to limit the seismic evidence of its tests.

The DF-61 intercontinental ballistic missile is seen during a military parade marking the 80th anniversary of the end of World War II, in Tiananmen Square, Beijing, on Sept. 3, 2025. Greg Baker/AFP via Getty Images

A top U.S. arms control diplomat on Feb. 6 accused China of carrying out secret nuclear weapons tests and called for the adoption of new measures to constrain nuclear arms.

“Today, I can reveal that the U.S. Government is aware that China has conducted nuclear explosive tests, including preparing for tests with designated yields in the hundreds of tons,” Under Secretary of State for Arms Control Thomas DiNanno said at an international arms control conference in Geneva on Friday.