President Biden blocked the deal between Nippon and U.S. Steel earlier this month due to "national security" concerns.

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.

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

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,

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.’’

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.

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

Blocking Nippon Steel from acquiring U.S. Steel lays the groundwork for a major consolidation of American steelmaking that will harm consumers and the economy.

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."

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