WASHINGTON, Sept. 16 -- Martin Dempsey, chairman of the U.S. Joint Chiefs of Staff said Tuesday that American ground troops could be called into battle against the Islamic State (IS) in Iraq and Syria if circumstances require.

So far, U.S. President Barack Obama has deployed about 1,600 military advisers to Iraq, but has stressed that the troops are not "boots on the ground" in a combat role.

However, Dempsey said Obama has ordered him to come back on a " case-by-case basis" if the use of ground forces need to be reconsidered.

"My view at this point is that this coalition is the appropriate way forward. I believe that will prove true. But if it fails to be true, and if there are threats to the United States then I, of course, would go back to the president and make a recommendation that may include the use of U.S. military ground forces," Dempsey said during a hearing of the Senate Armed Services Committee.

Dempsey said one circumstance that could require the use of ground troops would be if Iraqi or Kurdish forces were poised to retake Mosul, which IS forces captured in June.

"It could very well be part of that particular mission to provide close combat advising or accompanying for that mission," Dempsey said.

The general's remarks opened the door to increased American military involvement in Iraq at a time when liberals in Congress are increasingly anxious about President Obama's request to train rebel forces in Syria.

Dempsey emphasized that military actions would be "part of a whole of government effort that works to disrupt ISIL financing, interdict the movement of foreign fighters across borders, and undermine the ISIL message."

"Within a coalition of capable, willing regional and international partners, I believe we can destroy ISIL in Iraq, restore the Iraqi-Syrian border, and disrupt ISIL in Syria," he said. "ISIL will ultimately be defeated when their cloak of religious legitimacy is stripped away and the populations on which they have imposed themselves reject them."

According to the U.S. Central Command, U.S. military has conducted since Monday a number of airstrikes on IS targets southwest of Baghdad, part of the U.S.' expanded efforts, "beyond protecting our own people and humanitarian missions to hit ISIL targets as Iraqi forces go on offense," as outlined in Obama's Sept. 10 speech.

Since August 8, U.S. Central Command has conducted a total of 167 airstrikes across Iraq.