The United States accuses China of conducting a secret nuclear test in 2020

The United States accused Beijing on Friday of conducting a secret nuclear test in 2020. The accusation comes in the context of the U.S. calling for a broader nuclear treaty that would involve both Russia and China, after the New START treaty expired, but the proposal was rejected by Beijing, Reuters reports.

The accusations from a global disarmament conference highlighted serious tensions between Washington and Beijing at a crucial moment in nuclear arms control, just a day after the treaty limiting the deployment of missiles and nuclear warheads by the U.S. and Russia expired.

"I can reveal that the U.S. government is aware that China has conducted nuclear explosive tests, including preparing for tests with specified quantities in the hundreds of tons," said U.S. Under Secretary of State for Arms Control and International Security, Thomas DiNanno, at a Disarmament Conference in Geneva.

The Chinese military "has tried to conceal the tests by obscuring the nuclear explosions, as it has acknowledged that these tests violate test ban commitments. China has used 'decoupling', a method to reduce the effectiveness of seismic monitoring, to hide its activities from the world," he said.

Chinese disarmament ambassador, Shen Jian, dismissed the accusations, stating that the U.S. is amplifying the Chinese nuclear threat. The expiration of the New START treaty has left a void in nuclear arms control, and analysts warn that a world without strict regulations could become more dangerous. Russia has expressed a desire for dialogue with the U.S., but emphasized the need to include other nuclear powers in negotiations. In this context, international tensions are rising, and discussions about expanding nuclear arsenals are becoming increasingly relevant.