.Biden prepping to block Nippon Steel acquisition of united state Steel The Washington PostU.S. Steel states it could possibly leave behind Pittsburgh if Nippon deal falls through as Biden organizes to obstruct takeover Pittsburgh Post-GazetteBiden Expected to Block USA Steel Requisition The New York TimesExclusive|United State Steel Portend Vegetation Closings if Sale Breaks Down The Wall Street JournalBiden readied to block US Steel investment through Nippon Steel CNN.