About 400 soldiers from the 101st Airborne Division based in Fort Campbell, Kentucky, will deploy to Iraq as part of the military's effort to set up a logistics base at an airfield south of Mosul.

The soldiers are part of the 2nd Brigade Combat Team and are among the 560 additional troops that President Barack Obama approved for the Iraq mission last month.

The troops are establishing a logistics hub at Qayara air base, to help Iraqi forces prepare to retake the northern city of Mosul from Islamic State militants. IS seized the city in 2014.

The U.S. troop authorization for Iraq is 4,647. The Pentagon says there are about 3,800 U.S. forces there, not including hundreds who are on temporary duty and not included in the official count.