President Biden on Friday is expected to block Japan's Nippon Steel from acquiring U.S. Steel, citing national security concerns, the White House announced Friday. Why it matters: U.S. Steel's shares were down as much as 9% in pre-market trading Friday on the news.

President Joe Biden has rejected the nearly $15 billion proposed deal for Nippon Steel of Japan to purchase Pittsburgh-based U.S. Steel.

President Joe Biden said Friday he is blocking a $14.3 billion acquisition of US Steel by Japan’s Nippon Steel, marking a significant use of executive authority in the closing days of his administration.