By David Brunnstrom, Simon Lewis, Trevor Hunnicutt and Tim Kelly WASHINGTON/TOKYO (Reuters) -U.S. President Joe Biden's decision to block Nippon Steel's $14.9 billion bid for U.S. Steel cast a shadow over Secretary of State Antony Blinken's visit to Japan on Tuesday for farewell meetings with Washington's most important ally in Asia.

U.S. Steel and Japan’s Nippon Steel sued the United States government on Monday in a last-ditch attempt to revive their attempted merger after President Biden blocked it last week on the basis that the transaction posed a threat to national security.

Nippon Steel Chief Executive Eiji Hashimoto says the top Japanese steelmaker is standing firm on its proposed $15 billion acquisition of U.S. Steel.