The United States agreed last month to the Turkish government's request for support to secure the sovereignty of its airspace, Cook said, according to the official website of the U.S. Department of Defense.
The request came "on the heels of the incursions we saw by the Russians … and it's a request we've honored," Cook said.
The U.S. action reflects "both our commitment to ensure the safety of our NATO ally and our commitment to degrade and ultimately defeat the [Islamic State of Iraq and the Levant] in Iraq and Syria," he added.
The U.S. Air Force will also soon deploy F-15E Strike Eagle jets to Incirlik as part of the coalition's counter-ISIL operations, although their number and date of arrival are yet to be determined, Cook said.
Read alsoTurkey plans to launch military operation against ISIS"We commend Turkey's decision to open these [airspaces] to us and other coalition members participating in air operations against ISIL and Turkey's participation in coalition counter-ISIL air operations," he added.
The U.S. presence in Turkey includes U.S. personnel recovery assets and manned and remotely piloted aircraft already conducting counter-ISIL missions from Incirlik, Cook said.
Read alsoTurkey says downed drone was Russian-madeThe American fighter jets will join Turkish F-16s at Incirlik, which regularly participate in coalition counter-ISIL missions in Syria, including strike missions, he added.
"Beyond air operations, we continue our dialogue with Turkey to evaluate options on the most-effective means of countering ISIL, including along its borders in a manner that supports Turkey's security and regional stability," Cook said.
