US accuses China of secret nuclear tests in 2020

On Friday, February 6, the United States accused China of conducting a secret nuclear test in 2020, calling for a new, broader arms control treaty that would include both China and Russia. This was reported by the agency Reuters.

The accusations at the global disarmament conference highlighted serious tensions between Washington and Beijing at a crucial moment in nuclear arms control, one day after the expiration of a treaty limiting the deployment of missiles and warheads by the United States and Russia.

US Under Secretary of State for Arms Control Thomas DiNanno said during a disarmament conference in Geneva that the Chinese military had prepared and conducted a nuclear explosion with a capacity of "hundreds of tons" and used special methods to reduce the effectiveness of seismic monitoring.

He added that the Chinese military tried to conceal the tests by disguising the nuclear explosions, as they realized that these tests violated obligations. China used the "decoupling" method, which reduces the effectiveness of seismic monitoring, to hide its activities from the world.

DiNanno emphasized that China conducted one such "test with declared capacity" on June 22, 2020.

China's Ambassador for Disarmament Affairs Shen Jian did not directly respond to DiNanno's accusations, but said that Beijing has always acted prudently and responsibly on nuclear issues.

"China notes that the United States continues to inflate the so-called Chinese nuclear threat in its statements. China strongly opposes such false narratives," he said, accusing Washington of escalating the arms race.

Diplomats at the conference said the U.S. accusations were new and troubling. China, like the United States, has signed but not ratified the Comprehensive Nuclear-Test-Ban Treaty. Russia signed and ratified it, but withdrew its ratification in 2023.

• October 22, 2025 Russia conducts "nuclear exercises" and launched, in particular, a Yars missile at a test site on the border with the United States.
• October 30, Trump instructed the Pentagon to immediately begin testing American nuclear weapons.
• On December 24, it was reported that China may be getting ready to a "national total war" and by 2030 could possess about 1,000 nuclear warheads.