Turkey is an important NATO ally, the chief of the military alliance said Sunday, ruling out suspension of its membership amid a recent agreement over northern Syria.

“One must acknowledge that Turkey is an important ally,” NATO’s Secretary General Jens Stoltenberg told German weekly Bild am Sonntag and pointed out that Ankara has legitimate security interests.

“In the fight against ISIL [Daesh], Turkey has made crucial contributions for physically destroying the so-called caliphate. Furthermore: No other ally is hosting so many Syrian refugees, 3.6 million in total. And no other NATO ally has suffered more terrorist attacks than Turkey,”

Read more: NATO chief: Turkey is an important ally