.Biden preparing to block Nippon Steel investment of united state Steel The Washington PostU.S. Steel says it could possibly leave Pittsburgh if Nippon deal fails as Biden intends to block takeover Pittsburgh Post-GazetteBiden Expected to Block United State Steel Takeover The The Big Apple TimesExclusive|USA Steel Warns of Vegetation Closings if Purchase Falls Down The Wall Street JournalBiden prepared to block US Steel purchase by Nippon Steel CNN.