.Biden readying to block Nippon Steel purchase of united state Steel The Washington PostU.S. Steel says it could leave behind Pittsburgh if Nippon bargain fails as Biden prepares to block out requisition Pittsburgh Post-GazetteBiden Expected to Block United State Steel Takeover The The Big Apple TimesExclusive|USA Steel Portend Plant Closings if Sale Breaks Down The Exchange JournalBiden prepped to block out United States Steel purchase by Nippon Steel CNN.