.Biden prepping to block Nippon Steel acquisition of U.S. Steel The Washington PostU.S. Steel mentions it can leave Pittsburgh if Nippon deal fails as Biden plans to shut out takeover Pittsburgh Post-GazetteBiden Expected to Block USA Steel Takeover The Nyc TimesExclusive|USA Steel Warns of Vegetation Closings if Purchase Breaks Down The Exchange JournalBiden prepared to shut out United States Steel acquisition by Nippon Steel CNN.