The Biden administration took steps on Wednesday to prevent China from circumventing American tariffs on Chinese steel and aluminum by routing those imports through Mexico.

The administration said it would impose tariffs on imports of Mexican metals that are partially made in China. American officials said the move would close a trade loophole that has allowed cheap, state-subsidized Chinese metals to circumvent existing U.S. tariffs.

The United States will now impose a 25 percent tariff on Mexican steel that is melted or poured outside of North America before being turned into a finished product. Previously, that steel would have entered the country duty free.

Mexican aluminum coming into the United States will face a tariff of 10 percent if it contains metal that has been smelted or cast in China, Belarus, Iran or Russia, said Lael Brainard, the director of the White House’s National Economic Council.

Mexico, which recently increased its own tariffs on steel and aluminum from certain countries, will require importers to provide more information about where their steel products come from, the announcement said. The changes will take effect immediately.

Officials in the Biden administration said the United States wanted to protect American factories that produce steel and aluminum, including those that have recently received new investments from government funds.