(VOVworld) - US President Barack Obama and his Turkish counterpart Recep Tayyip Erdogan vowed to step up the fight against the Islamic State (IS) group and strengthen Syria’s moderate opposition.

Obama spoke to Erdogan by phone (Photo: AFP)

In a telephone talk on Friday, the two leaders reaffirmed their shared goal of stepping up military pressure on IS and strengthening moderate opposition elements in Syria to create conditions for a negotiated solution to the conflict, including a political transition. Obama and Erdogan stressed the "urgent need for an end to PKK attacks in Turkey," the White House said, while Obama "offered condolences as well as US solidarity in the face of the security threats Turkey faces".