Parts of restive northern Iraq remain under insurgent control , attacks continue . Iraq says it will not extend June 30 deadline for U.S. troops to leave cities . Mosul last major battleground since troop surge forced insurgents out of Baghdad . Top U.S. commander in Iraq says potential exists for Iraq to handle mission .
Parts of restive northern city remain under insurgent control , attacks continue . Iraq says it will not extend June 30 deadline for U.S. troops to leave cities . Mosul last major battleground since troop surge forced insurgents out of Baghdad . Top U.S. commander in Iraq says potential exists for Iraqis to handle mission .