ANKARA, Turkey — NATO allies extensivelydiscussed potential means to fight radical Islamist terrorism at a NATOsummit in Turkey, agreeing to seek a more concerted action in their warfight against onthe Islamic State of Iraq and the Levant (ISIL).

NATO Secretary-General Jens Stoltenberg pledged that the alliance would examine "all possibilities" against ISIL terrorism. The jihadist group has taken large swathes of land in Syria and Iraq since last summer.

"One of the important issues at this meeting, in different formats, will be how NATO can do even more in fighting terrorism and in fighting ISIL," Stoltenberg told reporters before the meeting.

Turkey urged its allies to do more and highlighted its own fragile position.

"The Daesh threat grows, we see an increasing violence of terrorism at our doorstep," Turkish Prime Minister Ahmet Davutoglu said, using the Arabic acronym of the jihadist group. "Being the only NATO country that shares a land border with Daesh-controlled areas, this terrorist organization is a direct threat to our national security."

US Secretary of State John Kerry said that defining a clearer security arrangement between Gulf countries and the United States is critical to fighting terrorism.

"Defining ... a clearer defense arrangement between the GCC and other friendly countries and the US is going to be critical to helping to push back against terrorism, violence and some of the other activities that take place in the region that are unsettling all of those countries," said Kerry.

Meanwhile, Gen. Philip Breedlove, NATO supreme allied commander and head of US European Command, Philip Breedlove visited a US training team in Turkey that runs, together with Turkey, a train-and-equip program for moderate Syrian fighters.

He said: "I was impressed with the team and with the facilities provided by the Turkish military. I was impressed with the preparations of the team, their understanding of the mission and supplies."