US Defense Secretary Jim Mattis has called on Ankara to remain focused on fighting Islamic State (IS, formerly ISIS) militants in Syria. According to a Pentagon statement on Thursday, Mattis met his Turkish counterpart on the sidelines of a NATO meeting in Brussels. He called for “a renewed focus on the campaign to defeat IS, and to preventing any vestige of the terrorist organization from reconstituting in Syria,” Reuters reported. Last month, Turkey launched a military incursion into the Kurdish-held Afrin region of Syria to sweep the Kurdish YPG militia from its southern border zone.