The US had accused China of conducting a secret nuclear explosive test in June 2020, shortly after the deadly Galwan Valley clashes.

This allegation, revealed at a global disarmament forum, heightens India's strategic concerns over China's military posture amidst ongoing border tensions. China denies the claims, accusing the US of exaggerating threats and fuelling an arms race.

However, China has firmly rejected recent US accusations of conducting secret nuclear explosive tests, labelling the claims as "outright lies" and accusing Washington of fabricating pretexts to justify its own nuclear activities. The denial came from Beijing's Ministry of Foreign Affairs on Monday, amid escalating rhetoric at international forums.

The controversy erupted at the UN Conference on Disarmament in Geneva last Friday. Thomas DiNanO, the US Under Secretary of State for Arms Control, directly accused China of carrying out a nuclear test on 22 June 2020, along with preparations for further tests involving massive yields. He presented these allegations as part of a broader US push for transparency in global nuclear programmes.

China's response was swift and unequivocal. A ministry spokesperson told AFP that the US claims were "completely groundless" and represented a deliberate attempt to shift blame. Beijing urged Washington to cease its "irresponsible actions" immediately, framing the dispute as a distraction from America's own nuclear ambitions.

This exchange occurs against the backdrop of fraying arms control frameworks. The New START treaty, the last major agreement limiting deployed nuclear warheads between the US and Russia, expired last Thursday. Without renewal, stockpiles could expand unchecked, heightening risks of an arms race.

US President Donald Trump amplified tensions in October by announcing that Washington would resume nuclear testing "on an equal basis" with Moscow and Beijing. He offered no specifics on the type or scale of tests, but the statement signalled a potential reversal of the US testing moratorium in place since 1992.

DiNanO's Geneva speech also unveiled a new US proposal for trilateral talks involving Russia and China. The plan aims to establish fresh limits on nuclear arsenals, addressing gaps left by New START's demise. However, China's scepticism suggests Beijing views it as a ploy rather than genuine diplomacy.

Nuclear testing remains a flashpoint in superpower relations. The Comprehensive Nuclear-Test-Ban Treaty (CTBT), adopted in 1996, bans all explosive tests but lacks full ratification—neither the US nor China has approved it, though both observe a voluntary moratorium. The US alleges China violated this norm, citing seismic data and satellite imagery from its own monitoring networks.

Experts note that advanced computer simulations have largely replaced live tests for major powers, reducing the need for explosions. Yet suspicions persist: the US points to China's rapid expansion of its arsenal, now estimated at over 500 warheads, as evidence of covert activities to refine designs.

China, in turn, accuses the US of hypocrisy. Beijing highlights America's historical dominance in testing—over 1,000 detonations since 1945 compared to China's 45—and its recent investments in modernising warheads like the W87-1. Chinese state media has portrayed Trump's rhetoric as aggressive posturing ahead of domestic political pressures.

The timing of the accusations aligns with broader US-China frictions, including trade disputes, technology rivalries, and South China Sea tensions. Arms control has become another arena for strategic competition, with each side seeking leverage.

Russia, meanwhile, watches closely. Moscow let New START lapse without extension, citing US missile deployments in Europe and Asia. President Vladimir Putin has expressed openness to talks but insists on including hypersonic weapons and missile defences in any pact.

For global non-proliferation efforts, the impasse is alarming. The CTBT's verification regime, including over 300 international monitoring stations, detects anomalies worldwide—such as the 2020 event the US attributes to China near its Lop Nur site. Independent seismologists have debated its nature, with some suggesting it was a sub-critical test, not a full explosion.

Sub-critical tests, which do not produce a nuclear chain reaction, are permitted under most interpretations of moratoria. The US conducts these routinely at its Nevada site, fuelling China's counter-claims of double standards.

As trilateral talks loom, analysts predict tough negotiations. China demands parity in warhead counts before caps, while the US and Russia seek verifiable limits on all delivery systems. Failure could spur a new era of testing, undermining decades of restraint.

The UN Conference on Disarmament, dormant on major accords since 1996, now hosts this pivotal drama. Smaller nuclear states like India and Pakistan observe warily, fearing erosion of taboos that bolster their own postures.

In Beijing, officials reiterate commitment to a nuclear-free world but tie progress to US restraint. Washington's pushback emphasises verification as trust's cornerstone, amid intelligence reports of China's underground tunnel networks potentially masking tests.

This episode underscores the fragility of deterrence in a multipolar nuclear order. With New START gone and testing bans unratified, the risk of miscalculation rises. Diplomatic off-ramps remain, but mutual accusations may foreclose them.

Based On AFP Report