.Biden preparing to obstruct Nippon Steel purchase of USA Steel The Washington PostU.S. Steel mentions it could leave Pittsburgh if Nippon offer falls through as Biden considers to obstruct takeover Pittsburgh Post-GazetteBiden Expected to Block U.S. Steel Takeover The New York City TimesExclusive|USA Steel Portend Plant Closings if Purchase Breaks Down The Stock market JournalBiden readied to obstruct United States Steel acquisition by Nippon Steel CNN.