President Donald Trump has threatened to pile an additional 40% tariff on any product that Washington determines to be “transshipped” through another country, a punishment aimed at stopping goods mainly from China dodging US duties.

The U.S. Court of Appeals for the Federal Circuit in Washington, D.C., will consider the legality of "reciprocal" tariffs that Trump imposed on a broad range of U.S. trading partners in April, as well as tariffs imposed in February against China,

Trump's sweeping tariffs are set to go into effect Friday. Since he postponed the biggest hikes in April because of market turmoil, Trump has announced an array of tariff levels with about a dozen trading partners.

The U.S.-Chinese cease-fire left exporters with crippling tariffs, worsening a slowdown for light-industry factories caused by China’s shift to advanced manufacturing.