U.S. and Iraqi Defense Officials held a press conference at the Pentagon on Thursday, where they discussed what the liberation of Mosul means for the ongoing war effort against the Islamic State and related extremists.

The press conference saw participation from Iraqi Brig. Gen Yahya Rasool, spokesman for the Joint Operations Command; Brig. Gen. Halgurd Hikmat Ali, the spokesman for the Kurdistan Regional Government’s Ministry of the Peshmerga; and Brig. Gen Saad Maad, spokesman for the Baghdad Operations Command and Iraq’s Interior Ministry.

Army Col. Ryan Dillon, the spokesman for Combined Joint Task Force Operation Inherent Resolve, explained to reporters that the recapture of Mosul dealt the terrorist organization a “significant blow,” but warned that there are still serious challenges ahead in the fight against ISIS.  Dillon also emphasized the “Iraqi determination” that he said has placed ISIS on the rapid decline.

“Iraqi security forces, on the other hand, have only improved and gotten stronger,” the colonel said. “They have proven with their battlefield successes that they know … they are a better fighting force and they are better than the terrorists that they fight.”