WASHINGTON (AP) — The Army's retiring top officer says the time may come when the U.S. should consider embedding American forces in Iraqi units to help advise them.

Gen. Raymond Odierno (oh-dee-EHR'-noh) is raising the option if American officials conclude that Iraqi forces aren't making enough progress against Islamic State militants — even with the support of U.S. and coalition airstrikes.

The Army's chief of staff says that doesn't mean U.S. forces would be directly involved in the fighting. But he says it's an option the president should hear.

Odierno was conducting his final Pentagon briefing with reporters before he retires on Friday after 43 years.

He served three tours in Iraq and led the 4th Infantry Division during the 2003 invasion. He was the top military commander in Iraq from 2008-2010.