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.

In blocking the sale to Nippon Steel, Biden said U.S. Steel "will remain a proud American company – one that’s American-owned and American-operated."

Separate lawsuits from Nippon Steel and U.S. Steel target President Joe Biden as well as a steelworkers union head and a rival steelmaker’s CEO.

President Joe Biden officially announced on Friday he has blocked Nippon Steel's $14.1 billion purchase of U.S. Steel, setting up a likely federal court battle.

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

Critics of the proposed purchase were worried about potential job losses for American workers and the foreign ownership of a longtime American company.

Trump opposes U.S. Steel's sale to Nippon, but CEO David Burritt believes he can convince the president-elect that the deal is in the interest of U.S. workers.

President Joe Biden on Friday announced his decision to block the $14 billion sale of U.S. Steel to Japan’s Nippon Steel, citing national security concerns. The move could have serious implications in Gary,

Both Biden and President-elect Donald Trump have courted unionized workers at U.S. Steel and vowed to block the acquisition amid concerns about foreign ownership of a flagship American company.

U.S. Treasury Secretary Janet Yellen said on Wednesday that Nippon Steel's blocked acquisition of U.S. Steel received a "thorough analysis" by an interagency national security review body that was sent to President Joe Biden.

A 123-year-old steelmaker’s fate could yet become a restraint on modern-day executive power. United States Steel and suitor Nippon Steel have gone to court over U.S. President Joe Biden’s decision to nix their $15 billion deal.