Turkey to Allow Use of Key Air Bases for U.S. Warplanes to Bomb ISIS

AMMAN, Jordan — The United States and Turkey have reached an agreement for manned and unmanned American warplanes to carry out aerial attacks on the Islamic State from two Turkish air bases, Obama administration officials said Thursday.

The agreement on the bases, Incirlik and Diyarbakir, was described by one senior administration official as a “game changer” that would significantly strengthen the American military’s ability to strike at ISIS targets in Syria and carry out extended aerial surveillance. It came after months of negotiations that culminated on Wednesday with a phone call between President Recep Tayyip Erdogan of Turkey, and President Obama, another administration official said.

The development came as Turkish forces were reported to have engaged in the first direct combat with Islamic State forces on the Syrian side of the border.

Both developments vaulted Turkey squarely into the broader battle with the Islamic State, also known as ISIS or ISIL. It was a step the Turkish authorities had been reluctant to take until now in their effort to protect Turkey’s border with Syria, where ISIS is firmly ensconced.

Turkey had allowed unmanned flights from Incirlik but had thus far balked at allowing manned airstrikes.

Officials at both the State Department and the Pentagon said they were hesitant to talk about the pact until the Turkish government acknowledged the agreement publicly. Turkish officials declined to comment on Thursday night.

The United States and Turkey “have decided to further deepen our cooperation in the fight against ISIL,” the State Department’s spokesman, John Kirby, said in an emailed statement. He said that “due to operational security I don’t have further details to share at this time.”

Mr. Kirby added that the United States would work with Turkey and other European partners to curb the flow of foreign fighters to Syria, recognizing that “the foreign fighter problem is not Turkey’s alone.”

The clash between Turkey’s armed forces and ISIS came after gunmen identified by Turkish news media as ISIS fighters opened fire on a Turkish border outpost in the Kilis region, killing one Turkish soldier and wounding five.

Turkey’s semiofficial Anadolu news agency and other agencies said the military scrambled fighter jets and hit suspected ISIS targets on the Syrian side of the border with tanks and artillery. At least one ISIS militant was killed and a number of ISIS vehicles were destroyed, the accounts said.

The clash came two days after a suicide bomber with suspected ties to ISIS struck a cultural center in the Turkish border town of Suruc, killing 32 people and wounding more than 100. That bombing was one of the worst in Turkey in many years.

Obama administration officials said that the United States had agreed to work with European allies, including Germany, France and Britain, to do more to control their end of the flow of foreign fighters into Turkey.

It was unclear what other concessions might have been made by the United States to get the deal, but a NATO official said on Thursday that “the Turks always drive a hard bargain.”

The breakthrough came after talks in Turkey last week between Gen. John R. Allen, a retired Marine who is President Obama’s special envoy for the fight against ISIS, and Turkish counterparts. General Allen’s trip was preceded by a telephone call from Vice President Joseph R. Biden Jr. to Mr. Erdogan, administration officials said.

A senior Defense Department official said recent attacks by ISIS on Turkish targets had played an important role in Turkey’s decision to deepen its role in the fight against the militant organization.

“Attacks in Turkey are part of the catalyst for them to think about how they get in the game,” the official said, speaking on grounds of anonymity.

For the Pentagon, the Turkish decision is huge because the two air bases are so much closer to the Syrian border than Iraq, Kuwait, Jordan and the Persian Gulf, where strikes had been launched. The agreement will significantly increase the amount of time that American spy planes can hover over Syria. In addition, it will speed up the response time for manned flights acting on intelligence.

But even as they were lauding the agreement, American military officials were cautious because they felt that they had been burned by Turkey before.

In 2003, Defense Department officials believed they had an agreement with the Turks to launch the Army’s 4^th Infantry Division into northern Iraq from Turkey as part of the invasion of Iraq. But the Turkish Parliament refused to grant permission for the operation and the division’s equipment remained offshore on ships.