The Communist Chinese government could be conducting secret, low-powered nuclear tests despite claiming that it was honoring an international agreement banning all nuke testing, the Wall Street Journal reported Wednesday.

A new arms-control report coming from the State Department cites actions that “raise concerns” that Beijing might not be complying with the “zero-yield” nuclear weapons testing ban, the paper reported.

The concerns stem from increased activity at China’s Lop Nur test site, including extensive excavations, and Beijing’s suspected use of special chambers to contain explosions.

Also fueling US suspicions is the interruption in recent years of data transmissions from monitoring stations in China designed to detect radioactive emissions and seismic tremors.

The Trump administration’s allegation came in an unclassified summary of an annual review of international compliance with arms control accords.

The review will likely exacerbate existing strains over China’s handling of the coronavirus pandemic, its military build-up in the South China Sea and trade disputes.

It also comes as President Trump wants to open nuclear arms talks with Beijing in the hope of negotiating a new deal that also includes Russia and covers all nuclear weapons.

China’s embassy in Washington didn’t respond to the Journal’s requests for comment.

The agreement at the core of the dispute is the Comprehensive Nuclear Test Ban Treaty, which was concluded in 1996.

The accord allows testing and other activities to ensure the safety and reliability of nuclear weapons, including experiments involving fissile material, as long as they don’t produce a nuclear explosive yield.

The treaty isn’t legally in force because not enough nations have ratified it, though major powers, including the US and China, say they are abiding by its terms.

The US and China have signed the agreement but neither has ratified it.