NATO ministers, after a rare emergency meeting Tuesday, strongly backed Turkey's fight against the Islamic State after a series of deadly border attacks brought Ankara into the fight after more than a year of holding back.

"Terrorism poses a direct threat to the security of NATO countries and to international stability and prosperity. It is a global threat that knows no border, nationality, or religion – a challenge that the international community must fight and tackle together," the North Atlantic Council, NATO's governing body, said in a statement after the meeting in Brussels.

"Terrorism in all its forms and manifestations can never be tolerated or justified. The security of the alliance is indivisible, and we stand in strong solidarity with Turkey."

Turkey had requested the meeting in the wake of a July 20 suicide attack in the Syrian border town of Suruc that killed 32 people and was blamed on the Islamic State. Ankara last week also agreed to allow U.S. aircraft to use the Incirlik Air Base to bomb Islamic State targets in Syria — something Washington had sought for more than a year.

Tuesday's meeting was held under Article 4 of the 1949 North Atlantic Treaty, which requires consultations among alliance members "whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the parties is threatened."

Turkey had resisted joining the fight against the Islamic State in Syria, demanding first that the U.S. agree to create a "no-fly zone" along its border, something Washington reportedly has agreed to do, though U.S. officials publicly deny it.

"There's no imposition of a no-fly zone, and we're not considering one. But what is under consideration ... is deepening cooperation with our Turkish allies to counter [the Islamic State] in northwest Syria. We're going to continue to talk with them about how to do that," State Department spokesman John Kirby said.

He did however note that coalition warplanes already are operating in that area without opposition.

Turkish warplanes launched strikes against Islamic State targets in Syria over the weekend, but also hit targets belonging to the PKK, a leftist Kurdish group that has fought a guerrilla war against Ankara for years, potentially complicating the fight.

"We target those who target Turkey, not those who do not," Prime Minister Ahmet Davutoglu told Turkish television in an interview.