U.S. says new nuclear deal should include China, accuses Beijing of secret tests

U.S. Secretary of State Marco Rubio at the Capitol in Washington, Wednesday, Jan. 28, 2026. (AP Photo/J. Scott Applewhite)

The United States on Friday urged three-way talks with Russia and China to set new limits on nuclear weapons, as it accused Beijing of conducting secret nuclear tests and dramatically swelling its arsenal.

A day after the expiration of New START -- the last treaty between top nuclear powers Washington and Moscow -- Beijing reiterated that it did not plan to join disarmament negotiations “at this stage”.

Russia meanwhile suggested other nuclear-armed states such as Britain and France should be included in any talks.

“Arms control can no longer be a bilateral issue between the United States and Russia,” U.S. Secretary of State Marco Rubio wrote in an online essay.

“Other countries have a responsibility to help ensure strategic stability, none more so than China.”

The expiration on Thursday of New START, which restricted the United States and Russia to 1,550 deployed nuclear warheads each, marks the first time in decades that there is no treaty to curtail the positioning of the planet’s most destructive weapons, sparking fears of a fresh arms race.

U.S. President Donald Trump did not accept a proposal from Russian counterpart Vladimir Putin to keep New START’s restrictions in place for another year, and called Thursday for a “new, improved and modernized treaty”.

Secret nuclear tests?

Thomas DiNanno, U.S. under secretary of state for arms control, presented the new U.S. plan Friday to the Conference on Disarmament at the United Nations in Geneva, charging that the lapsed New START treaty had “fundamental flaws”.

He accused China of taking advantage of the “legally binding U.S.-Russian restraint to begin expanding its arsenal at a historic pace”, maintaining that it was “on track to have over 1,000 nuclear warheads by 2030”.

“As we sit here today, China’s entire nuclear arsenal has no limits, no transparency, no declarations, and no controls,” he said.

DiNanno also accused Beijing of conducting secret “nuclear explosive tests, including preparing for tests with designated yields in the hundreds of tonnes”.

He charged that one such test was conducted on June 22, 2020, and accused China of seeking “to conceal testing by obfuscating the nuclear explosions because it recognized these tests violate test ban commitments”.

Trump hinted at similar accusations late last year but without providing the same level of detail.

He said Washington wanted to resume testing nuclear weapons for the first time in decades “on an equal basis” with Moscow and Beijing but without elaborating and so far without following through.

‘Irresponsible’

China’s ambassador Shen Jian slammed Washington on Friday for “making irresponsible remarks, for instance the threatening of making nuclear weapons tests”.

He also reiterated Beijing’s official position, insisting to the conference that “China would not participate in nuclear disarmament negotiations at this stage”.

“States possessing the largest nuclear arsenals should continue to fulfil their special and primary responsibilities for nuclear disarmament,” he added.

Russia and the United States together control more than 80 per cent of the world’s nuclear warheads.

But China’s nuclear arsenal is growing faster than any other country, by about 100 new warheads a year since 2023, according to the Stockholm International Peace Research Institute.

Russia, which has said it no longer considers itself bound by New START limits, said any new nuclear talks should include other nuclear-armed states such as France and Britain, its ambassador Gennady Gatilov told Friday’s conference.

Britain’s ambassador, David Riley, appeared to dismiss the idea, saying “the United Kingdom maintains a minimum credible nuclear deterrent” and that arms control talks should focus on “those states with the largest nuclear arsenals -- China, Russia and the US”.

French ambassador Anne Lazar-Sury meanwhile said Paris believed “credible measures capable of reducing the risk of nuclear weapons use” should be “the objective of all nuclear-armed states.”

Trump has said New START was “badly negotiated” and “is being grossly violated”.

Russia in 2023 rejected inspections of its nuclear sites under the treaty, as tensions rose with the United States over Moscow’s invasion of Ukraine.

But Trump has resumed diplomacy with Putin’s Russia. The two countries on Thursday announced a resumption of direct military dialogue to avert crises.