The State Department's Office of Inspector General reported Thursday that almost one in three Iraqis believes the United States is secretly backing the Islamic State.

"Recent Department polling shows that about 40 percent of Iraqis believe that the United States is working to destabilize Iraq and control its natural resources," the report said. "Nearly a third believe that America supports terrorism in general or the Islamic State in Iraq and the Levant."

It also said that close to 50 percent of Iraqis now oppose the Western effort against the Islamic State.

"About half of Iraqi Sunnis and Shia now say that they completely oppose the Global Coalition to Counter the Islamic State in Iraq and the Levant," the report states.

"The U.S. image among Iraqis has fallen from 38 percent favorable in December 2014 to 18 percent in August 2015," the report added. "The drop is greater among Sunni Arabs, from 54 percent down to 10 percent."

The Islamic State is a Sunni entity.