The commander of U.S. military operations against Islamic State militants is offering a cautious assessment of progress, saying a weakened Iraqi army is making only incremental gains against the extremists.

On a more optimistically, Army Gen. Lloyd Austin said Friday that he believes the Iraqi government will successfully enlist the support of Sunni tribal leaders in Anbar province to turn the tide in that important region.

Austin, who commanded U.S. forces in Iraq in the final years of the 2003-2011 war, gave reporters at the Pentagon an overview of U.S.-led efforts in Syria and Iraq — his first since airstrikes in Iraq began Aug. 8.

As an example of fresh progress, Austin said Iraqi soldiers on Friday attacked north from Baghdad to Beiji (BAY'-zhee), home to Iraq's largest oil refinery.