U.S. Steel and the Japanese firm that had sought to acquire it are suing the Biden administration after the president announced he was blocking a proposed deal for the iconic American manufacturer.

Nippon Steel had promised to invest $2.7 billion in U.S. Steel’s aging blast furnace operations in Gary, Indiana, and Pennsylvania’s Mon Valley.

U.S. Steel and Japan’s Nippon Steel sued the United States government on Monday in a last-ditch attempt to revive their attempted merger after President Biden blocked it last week on the basis that the transaction posed a threat to national security.