.Biden preparing to block out Nippon Steel investment of united state Steel The Washington PostU.S. Steel claims it can leave behind Pittsburgh if Nippon bargain fails as Biden prepares to block requisition Pittsburgh Post-GazetteBiden Expected to Block USA Steel Takeover The Nyc TimesExclusive|USA Steel Warns of Plant Closings if Purchase Collapses The Wall Street JournalBiden readied to block US Steel acquisition by Nippon Steel CNN.