.Biden readying to block Nippon Steel investment of U.S. Steel The Washington PostU.S. Steel claims it can leave behind Pittsburgh if Nippon bargain flops as Biden considers to block out takeover Pittsburgh Post-GazetteBiden Expected to Block USA Steel Takeover The Nyc TimesExclusive|U.S. Steel Warns of Vegetation Closings if Sale Breaks Down The Wall Street JournalBiden readied to block out United States Steel purchase through Nippon Steel CNN.