.Biden preparing to shut out Nippon Steel purchase of U.S. Steel The Washington PostU.S. Steel claims it could leave behind Pittsburgh if Nippon deal fails as Biden considers to block takeover Pittsburgh Post-GazetteBiden Expected to Block U.S. Steel Takeover The Nyc TimesExclusive|U.S. Steel Warns of Plant Closings if Sale Falls Down The Commercial JournalBiden prepared to block US Steel purchase through Nippon Steel CNN.