.Biden prepping to obstruct Nippon Steel purchase of U.S. Steel The Washington PostU.S. Steel says it can leave Pittsburgh if Nippon offer falls through as Biden organizes to obstruct requisition Pittsburgh Post-GazetteBiden Expected to Block USA Steel Requisition The The Big Apple TimesExclusive|U.S. Steel Warns of Plant Closings if Purchase Falls Down The Commercial JournalBiden prepped to shut out US Steel acquisition through Nippon Steel CNN.