WASHINGTON – Sen. Joe Lieberman, attacked by fellow Democrats as being too close to the White House on the Iraq War, on Sunday called on Defense Secretary Donald Rumsfeld to resign but said the United States cannot “walk away” from the Iraqis.

Lieberman, the one-time Democratic vice presidential candidate, is running as an independent in Connecticut in his bid for a fourth term since losing the Democratic nomination to newcomer Ned Lamont, who harnessed voters’ anger against the war in Iraq.