The Trump administration is preparing to set a price floor and impose tariffs on polysilicon and related products, according to four people familiar with the plan, putting a material critical to solar panels and semiconductors at the center of U.S. efforts to compete with China on artificial intelligence and energy.

The decision, expected to come later this month, aims to protect U.S. polysilicon factories owned by Hemlock Semiconductor and Wacker Chemie from growing Chinese ambitions in the chip supply chain.

President Donald Trump’s yearlong national security investigation into polysilicon by the Commerce Department also has major implications for the growing domestic solar manufacturing industry at a time when the U.S. leader has rolled back federal support for renewable energy.