NATO’s secretary-general on Thursday praised Gulf nations for their role in fighting extremists in Syria and Iraq, and said tackling the threat the militants pose will require long-term multinational efforts.

Jens Stoltenberg made the comments during a visit to the tiny, energy-rich nation of Qatar to mark the 10-year anniversary of the Istanbul Cooperation Initiative, or ISI, a partnership between the alliance and four Gulf states.

He said it is important that the OPEC nation and other regional countries are playing a part in the fight against extremists. […]