China warned the US that a law banning imports from Xinjiang unless companies prove they’re free of forced labor would “severely” damage ties, escalating a dispute between the nations over human rights.

“If the act is implemented, it will severely disrupt normal cooperation between China and the US, and global industrial and production chains,” Foreign Ministry spokesman Zhao Lijian said Thursday at a regular press briefing in Beijing.

Zhao urged the US not to implement the Uyghur Forced Labor Prevention Act and otherwise trying to “hobble China’s development.” He added that “if the US insists on doing so, China will take robust measures to uphold its own rights and interests as well as its dignity.”

The comments set up a showdown between the world’s two-largest economies because the law is set to take effect on June 21. The Biden administration has signaled it’s prepared to take a tough stance enforcing the ban, with Customs and Border Protection officials warning companies on Wednesday the bar for clearing imports will be “very high.”

“If there’s a part or a piece of an input that is coming from the Xinjiang region, then that shipment will be considering containing forced labor and it will not be allowed into the country,” said Elva Muneton, acting executive director of the task force implementing the new law.

Under the act, the US assumes that anything made even partially in the western region of Xinjiang is produced with forced labor and can’t be imported unless companies can provide “clear and compelling evidence” otherwise.

The law passed by Congress in December steps up US efforts to combat China’s alleged repression of Uyghurs and other minorities in Xinjiang. Beijing has repeatedly denied accusations that China is forcing minorities to work against their will.