WASHINGTON (AFP) -- More than two thirds of Americans think President George W. Bush is mishandling events in Iraq and almost a third believe civil war there is imminent, according to a Harris Poll published Friday.

More U.S. adults are pessimistic about the situation in Iraq since the bombing of the Askariya shrine and the ensuing sectarian violence, a nationwide survey found.

Sixty-eight percent of those interviewed gave a negative rating of Bush's current handling of events in Iraq, and 30 percent were positive.

The president's ratings slipped from a previous survey in January, in which 61 percent were negative and 36 percent positive.

Asked about the possibility of a civil war in Iraq in the next six months, 30 percent of those polled said that such a war was very or extremely likely, with another 20 percent saying it was likely.

Sixty-one percent doubted that U.S. policy in Iraq would be successful, up from 55 percent in January, while only 20 percent were confident, compared with 26 percent previously.

The Harris poll confirmed an erosion of public support for Bush's policy in Iraq. A Gallup survey published Thursday showed support for keeping U.S. troops in Iraq had reached its lowest point since the U.S.-led invasion to topple Saddam Hussein on March 20, 2003.

Harris online surveyed 2,435 U.S. adults between March 8 and 14.