(Bloomberg) -- The U.S. said it found “conclusive evidence” that a Chinese company used forced labor to make extracts of the sweetener stevia, with American ports now directed to seize any shipments.

Customs and Border Protection now has “conclusive evidence” that Inner Mongolia Hengzheng Group Baoanzhao Agriculture, Industry and Trade Co. used convict, forced or indentured labor to make the products and that they’re being or are likely to be imported to the U.S., the agency said in an statement Tuesday.

Previously, in 2016, the agency temporarily detained these shipments based on “reasonable but inconclusive proof” of forced labor.

The move is the latest in a string where the U.S. is raising pressure on China over some companies’ alleged ill-treatment of some workers. In September, CBP said it plans a so-called withhold release order, or WRO, that will cover all cotton, textile and tomato products from the country’s northwestern Xinjiang region, where predominantly Muslim minority groups are allegedly being repressed. China’s Foreign Ministry has denied the allegations.

The CBP has already issued WROs against three Xinjiang-based hair-product and garment producers in 2020 and plans six more in addition to the blanket Xinjiang order.The WROs come on top of restrictions imposed on a growing number of Chinese companies that the U.S. Commerce Department has placed on its Entity List, which curbs the firms’ access to U.S. technology and commodities.

President Donald Trump, who blames China for the U.S. coronavirus outbreak, has vowed to decouple the world’s two biggest economies should he win a second term in the November election.

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