.Biden readying to obstruct Nippon Steel acquisition of U.S. Steel The Washington PostU.S. Steel says it could possibly leave Pittsburgh if Nippon bargain fails as Biden considers to block requisition Pittsburgh Post-GazetteBiden Expected to Block United State Steel Takeover The Nyc TimesExclusive|United State Steel Warns of Vegetation Closings if Sale Breaks Down The Commercial JournalBiden prepped to block US Steel investment by Nippon Steel CNN.