Seoul: U.S. President Donald Trump on Thursday signed a proclamation to impose a 15 percent tariff on polysilicon derivative products, a move that his aide claimed aims to protect America's polysilicon manufacturing, crucial for semiconductor production.

According to Yonhap News Agency, the tariff action will take effect 120 days after the signing, with the White House noting that South Korea's semiconductor industry has been closely observing the Trump administration's trade policies for potential impacts on its U.S. business activities. The proclamation arrives as the U.S. intensifies efforts to maintain its technological edge amid growing competition with China over advanced technologies, including artificial intelligence (AI).

In addition to the tariff, the proclamation includes the imposition of minimum import prices for imported polysilicon and its derivatives, set at $21 per kilogram for polysilicon, $100 per kg for polysilicon ingots and wafers, $0.22 per watt for solar cells, and $0.38 per watt for solar modules. The White House explained that the minimum price program intends to "create a level playing field for American producers of these strategic goods."

Trump enacted this latest tariff action under Section 232 of the Trade Expansion Act of 1962, granting the president authority to adjust imports when deemed a threat to national security. White House Staff Secretary William Scharf stated that the executive order is part of a series of trade and tariff actions under Section 232 designed to support domestic polysilicon manufacturing and protect it from overseas dumping and offshore threats.

Commerce Secretary Howard Lutnick emphasized polysilicon as a "foundational" product essential for making silicon wafers for AI chips. He remarked, "We're making the products here, but we need the supply chain here. So this will bring the supply chain here. We're setting prices so that the Chinese can't dump anymore, and we're setting tariffs to say (you) build it here."