WASHINGTON: US authorities are ready to implement a ban on imports from China's Xinjiang region when a law requiring it becomes enforceable later in June, a U.S. Customs official said on Wednesday, adding that a "very high" level of evidence would be required for an exemption.

U.S. President Joe Biden in December signed into law the Uyghur Forced Labor Prevention Act (UFLPA) in an effort to safeguard the U.S. market from products potentially tainted by human rights abuses in Xinjiang, where the U.S. government says China is committing genocide against Uyghur Muslims.

The law includes a "rebuttable presumption" that all goods from Xinjiang, where Chinese authorities established detention camps for Uyghurs and other Muslim groups, are made with forced labor, and bars their import unless it can be proven otherwise. 

China denies abuses in Xinjiang, a major cotton producer that also supplies much of the world's materials for solar panels, and says the law "slanders" the country's human rights situation.

Some U.S. lawmakers have supported requests by Customs and Border Protection (CBP) for more budget to effectively implement that provision, which goes into effect on June 21.

"We're all on a very tight timeframe," Elva Muneton, CBP's acting executive director for the UFLPA Implementation Task Force, said.

"The expectation is that we will be ready to implement the Uyghur act on June 21, and that we have the resources," Muneton told a webinar on enforcing the law. "So the question is, are we ready to implement? Yes, we are," she said.

Importers will have the option to re-export prohibited cargo back to the country of origin, and any exemptions to the presumption must be granted by the CBP commissioner and reported to Congress, Muneton said.

"It's important to know that the level of evidence that's going be required by the Uyghur act is very high," she said.

"It's going to require documentation, clear and convincing evidence, that the supply chain of the product that's being imported is free from forced labor."

CBP will be able to issue penalties against importers in the case of fraud, she said.

Beijing initially denied the existence of any detention camps, but then later admitted it had set up "vocational training centers" necessary to curb what it said was terrorism, separatism and religious radicalism in Xinjiang.