The news: A US government proposal to levy stiff fees on China-built cargo ships is running into fierce resistance from retailers, shipping companies, and other groups, who warn it would curb trade and raise prices for businesses and consumers.

The plan is “more of a threat than the tariffs, because of the impact it’s going to have on the supply chain,” Jonathan Gold, the National Retail Federation’s vice president of supply chain, told Bloomberg.

The proposal: Under the Office of the US Trade Representative (USTR)’s plan, carriers could be forced to pay as much as $3.5 million in fees each time they dock at a US port. That includes a $1.5 million fee for ships built in China, $1 million for vessels operated by Chinese companies, and another $1 million if the operator plans to source over 50% of future ships from China.