President Joe Biden will reportedly officially block the purchase of U.S. Steel by Japan’s Nippon Steel due to concerns that the purchase could threaten national security. The president’s decision is expected to be announced as early as Friday. The Japanese corporation had offered to acquire the company for $14.9 billion.

Biden’s decision to block the deal stems from the findings of a Dec. 23 report from the Committee on Foreign Investment in the United States, the Washington Post reported. In its assessment, CFIUS concluded that the purchase could potentially reduce national steel productivity, causing “risks to the national security of the United States.” The president has been a staunch opponent of the deal since it was announced.