The United States has openly accused China of a substantial and rapid expansion of its nuclear arsenal, a claim that underscores growing tensions between the two powers. U.S. officials allege that China has conducted secret nuclear tests, an assertion that adds to fears that the absence of significant nuclear treaties between major powers, such as the lapsed New Start treaty with Russia, could lead to an arms race. Claims were made during a discussion at the Conference on Disarmament in Geneva by Christopher Yeaw, assistant secretary of state for arms control and non-proliferation, who described the existing nuclear agreements as inadequate given the current realities of global nuclear dynamics.

Yeaw highlighted the flawed nature of the New Start treaty, suggesting it failed to account for China’s unprecedented and opaque buildup of nuclear weapons. The U.S. government is keen to negotiate a new agreement that involves not only the U.S. and Russia but also China, recognizing that China's growing arsenal poses a strategic challenge. This rhetoric emphasizes a shift in U.S. policy as they seek to address the evolving nuclear landscape and come to terms with China's expanding military capabilities.

In response, China's ambassador to the conference, Shen Jian, rejected the accusations made by the U.S. and accused Washington of distorting Beijing's nuclear policy. The back-and-forth between U.S. and Chinese diplomats illustrates the rising friction in international relations, with potential implications for global security and arms control efforts. The allegations and counter-claims mark a critical moment in the discourse on nuclear proliferation and bilateral relations, as both nations navigate their strategic interests in an increasingly multipolar world.