.Biden preparing to obstruct Nippon Steel acquisition of U.S. Steel The Washington PostU.S. Steel states it could leave behind Pittsburgh if Nippon package falls through as Biden prepares to block out requisition Pittsburgh Post-GazetteBiden Expected to Block USA Steel Takeover The New York City TimesExclusive|United State Steel Warns of Vegetation Closings if Sale Collapses The Exchange JournalBiden readied to block United States Steel acquisition through Nippon Steel CNN.