President-elect Trump has also opposed Nippon Steel's $15 billion acquisition of U.S. Steel, which President Biden blocked last week.

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 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.

U.S. Steel and Nippon Steel said on Monday that it is suing over President Joe Biden's decision to block its sales agreement and a domestic competitor and union over their actions to scuttle the deal.

In dual lawsuits filed Jan. 6, U.S. Steel Corp. and Nippon Steel Corp. blame the Biden administration's politicizing its national-security review as well as the behind-the-scenes actions by rival Cleveland-Cliffs Inc. and United Steelworkers International President David McCall for scuttling the $14.9 billion deal.

In a joint statement, Nippon and U.S. Steel called Biden’s decision “a clear violation of due process and the law’’ and suggested they would sue to salvage their deal: “We are left with no choice but to take all appropriate action to protect our legal rights.’’

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,

Nippon Steel Corp. and U.S. Steel filed federal lawsuits Monday challenging the Biden administration’s decision as ignoring “the rule of law.”

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.

The companies condemned the president's decision and hinted at taking legal action, while U.S. Steel's CEO accused Biden of "political corruption."

President Joe Biden is reportedly close to deciding to block Nippon Steel’s $14.9 billion acquisition of United States Steel Corp., more than a year after it was announced and after opposition from the United Steelworkers and others.