Appearing at a briefing with Secretary of Defense Ash Carter, Chairman of the Joint Chiefs Gen. Joseph Dunford said, "The secretary and I both believe that there will be an increase to the U.S. forces in Iraq in the coming weeks."
Dunford added that a final decision on any troop deployments had yet to be made.
Most analysts think the additional forces will be deployed to help the Iraqi military in its upcoming campaign to liberate the major city of Mosul from ISIS control.
"Mosul is the primary target in 2016," Nick Heras of the Center for a New American Security told CNN.
Heras said, "Taking Mosul will require more fighters than the Iraqi security forces have and those new forces have to be trained," thereby requiring the additional U.S. presence.
A U.S. defense official told CNN earlier this week that the U.S. currently has between 4,500 and 5,000 troops in Iraq on a regular basis, about 1,000 over the stated limit of 3,800. This includes 200 Special Operations Forces whose presence is not publicly acknowledged, the official said.
The coalition has made a decision not to publicly reveal the exact number of U.S. troops currently in Iraq, coalition spokesperson Army Col. Steve Warren told reporters earlier this week.
Dunford acknowledged that there were sometimes more than 3,800 American troops in Iraq, but he attributed the discrepancy to units that were overlapping during rotations, embassy personnel and service members assigned to temporary in-country duties.
He said, "the accounting of our people has been consistent" over the last 15 years of military operations in Iraq and Afghanistan.