.Biden prepping to block out Nippon Steel investment of USA Steel The Washington PostU.S. Steel claims it might leave behind Pittsburgh if Nippon bargain falls through as Biden organizes to block out takeover Pittsburgh Post-GazetteBiden Expected to Block U.S. Steel Takeover The Nyc TimesExclusive|U.S. Steel Warns of Plant Closings if Purchase Breaks Down The Exchange JournalBiden readied to shut out United States Steel purchase by Nippon Steel CNN.