.Biden prepping to obstruct Nippon Steel investment of USA Steel The Washington PostU.S. Steel mentions it could leave Pittsburgh if Nippon deal fails as Biden considers to block requisition Pittsburgh Post-GazetteBiden Expected to Block USA Steel Requisition The Nyc TimesExclusive|USA Steel Portend Vegetation Closings if Purchase Breaks Down The Commercial JournalBiden readied to block United States Steel purchase through Nippon Steel CNN.