.Biden preparing to block out Nippon Steel purchase of united state Steel The Washington PostU.S. Steel mentions it can leave Pittsburgh if Nippon package fails as Biden plans to shut out requisition Pittsburgh Post-GazetteBiden Expected to Block USA Steel Requisition The New York TimesExclusive|USA Steel Warns of Plant Closings if Sale Falls Down The Stock market JournalBiden prepared to obstruct United States Steel acquisition through Nippon Steel CNN.