US Defence Secretary, Robert Gates, has told US troops in Iraq their mission there is now in its 'end game'.
He says the American military presence remains vitally important during the crucial transition period, but American combat troops will leave Iraqi cities during the next six months.
Mr Gates was speaking at a US airbase north of Baghdad.
He says US troops will need to be out of urban areas by June 30 and that represents a significant change in mission.
Mr Gates says US commanders in Iraq believe that by June 30 all 18 provinces will have been turned over to provincial Iraqi control.