The companies argued in a lawsuit announced on Monday that Biden violated the Constitution by blocking the merger via a sham national security review that deprived the companies of their right to a fair process.

President Joe Biden's decision to reject a bid by Nippon Steel to acquire U.S. Steel isn't the first time friction over trade and investment has irked Washington's closest ally in Asia.

U.S. Steel and Nippon Steel said Monday they are suing the U.S. government over President Joe Biden’s blocking last week of the $14.1 billion sale of the iconic American company to the Japanese firm on national security grounds.