A senior U.S. official has revealed what he described as new details about an alleged underground nuclear test conducted by China in June 2020.
Speaking on Tuesday at the Hudson Institute in Washington, Assistant Secretary of State Christopher Yeaw said fresh analysis pointed to a nuclear explosion at China’s Lop Nor test site in western China.
Seismic Data Points To Explosion
Yeaw stated that a remote seismic station in Kazakhstan recorded an event of magnitude 2.75 on June 22, 2020. The station detected the disturbance roughly 450 miles from the Lop Nor test grounds.
According to Yeaw, further review of the data strengthened his assessment. He said there was very little possibility that the event represented anything other than a single explosion. Moreover, he argued that the seismic signature did not match mining blasts.
“It’s also entirely not consistent with an earthquake,” Yeaw said. He added that the data aligned with what one would expect from a nuclear explosive test.
However, the Comprehensive Nuclear-Test-Ban Treaty Organization, which monitors compliance with the global ban on nuclear testing, said it lacked sufficient information to confirm the allegation with confidence.
The organisation’s executive secretary, Robert Floyd, explained that the PS23 seismic station recorded two very small seismic events spaced 12 seconds apart. He noted that these events fell well below the threshold typically associated with detectable nuclear test explosions.
As a result, Floyd said the available data alone did not allow a confident assessment of the cause.
China Rejects Allegations
In response, a spokesperson for the Chinese embassy in Washington dismissed the claim as entirely unfounded. The spokesperson accused the United States of attempting to fabricate excuses for resuming its own nuclear testing.
The statement described the allegation as political manipulation aimed at pursuing nuclear hegemony and evading disarmament responsibilities. Furthermore, China urged the United States to reaffirm the commitment of the five recognised nuclear weapon states to refrain from nuclear tests.
China has signed but not ratified the 1996 treaty banning nuclear testing. It denies conducting any underground nuclear blast in 2020 and says its last official underground test took place in 1996.
Treaty Tensions And Strategic Concerns
Meanwhile, U.S. President Donald Trump has pressed China to join the United States and Russia in negotiating a replacement for New START, the last strategic nuclear arms limitation agreement between Washington and Moscow, which expired on February 5.
The treaty’s expiration has fuelled concerns about a renewed nuclear arms race. Although both China and the United States have signed the nuclear test ban treaty, neither country has ratified it. Under international law, they remain obligated to uphold its provisions.
Yeaw also alleged that China may have attempted to conceal the test through decoupling. In this method, operators detonate a device inside a large underground chamber to reduce the shockwaves transmitted through surrounding rock.
The United States last conducted an underground nuclear test in 1992. Since then, it has relied on advanced simulations and scientific programmes to maintain its nuclear arsenal.
China has rejected calls to join a three way arms control pact, arguing that its arsenal remains far smaller than those of Washington and Moscow. However, the Pentagon says China now holds more than 600 operational warheads and projects that the figure could exceed 1,000 by 2030.
With inputs from Reuters
