.Biden prepping to block Nippon Steel investment of U.S. Steel The Washington PostU.S. Steel states it can leave behind Pittsburgh if Nippon bargain falls through as Biden intends to shut out takeover Pittsburgh Post-GazetteBiden Expected to Block U.S. Steel Requisition The New York TimesExclusive|United State Steel Warns of Vegetation Closings if Purchase Breaks Down The Commercial JournalBiden readied to block out US Steel purchase by Nippon Steel CNN.