.Biden prepping to block out Nippon Steel acquisition of U.S. Steel The Washington PostU.S. Steel says it might leave Pittsburgh if Nippon package fails as Biden organizes to block requisition Pittsburgh Post-GazetteBiden Expected to Block United State Steel Requisition The New York TimesExclusive|USA Steel Warns of Plant Closings if Purchase Breaks Down The Exchange JournalBiden prepped to shut out United States Steel acquisition by Nippon Steel CNN.