.Biden preparing to shut out Nippon Steel purchase of USA Steel The Washington PostU.S. Steel says it could possibly leave Pittsburgh if Nippon package fails as Biden intends to obstruct requisition Pittsburgh Post-GazetteBiden Expected to Block USA Steel Requisition The New York TimesExclusive|USA Steel Warns of Plant Closings if Purchase Collapses The Exchange JournalBiden readied to block United States Steel investment by Nippon Steel CNN.