.Biden readying to block out Nippon Steel acquisition of U.S. Steel The Washington PostU.S. Steel states it could leave Pittsburgh if Nippon bargain falls through as Biden organizes to obstruct takeover Pittsburgh Post-GazetteBiden Expected to Block United State Steel Takeover The Nyc TimesExclusive|USA Steel Portend Plant Closings if Sale Collapses The Exchange JournalBiden readied to obstruct US Steel investment through Nippon Steel CNN.