WASHINGTON, Sept 1 (Reuters) - U.S. House Speaker Nancy Pelosi said after a phone call with Treasury Secretary Steven Mnuchin on Tuesday that "serious differences" remain between Democrats and the White House over coronavirus relief legislation.

"Sadly, this phone call made clear that Democrats and the White House continue to have serious differences understanding the gravity of the situation that America's working families are facing," Pelosi said in a statement. (Reporting by Eric Beech; Editing by Sandra Maler)