The suit, filed in the U.S. Court of Appeals for the District of Columbia, alleges that it was a political decision and violated the companies’ due process.

Mr. Biden says he blocked the $14 billion takeover of U.S. Steel by Japan's Nippon Steel on the grounds the sale was a threat to national security.

The Vice-Chairman of Nippon Steel on Monday met with the mayors of the Mon Valley at Kelly’s Garage to talk about the Japanese company’s proposed nearly $15 billion acquisition of U.S. Steel.