Why China’s nuclear arsenal is under fire as US-Russia pact falls apart

An international organisation responsible for monitoring global nuclear testing has denied allegations by the United States that China has conducted secret nuclear tests.The Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), the global body tasked with detecting nuclear explosions, said its monitoring system “did not detect any event consistent with the characteristics of a nuclear weapon test explosion” at the time of the alleged Chinese test.Robert Floyd, the body’s executive secretary, said in a statement the same day that more detailed analyses supported the CTBTO’s assessment.The United States on Friday accused China of failing to disclose a 2020 nuclear test, an act a US official said violated an understanding involving a 1996 test ban treaty. Although both countries signed the pact, neither has ratified it.The timing of the US accusation highlights the tensions over a collapsing global arms control framework and anxieties over the scale of Beijing’s nuclear capabilities.This accusation came as the US declined to extend its New Start strategic arms reduction treaty with Russia and called upon China to join a new three-way nuclear arms control effort – a proposal Beijing has rejected, stating its nuclear arsenal was much smaller than those of Washington and Moscow.