The U.S. on Monday urged Turkish troops and Kurdish forces in northern Syria to halt their fighting, saying it hinders efforts to defeat the Islamic State group. But Turkey's president vowed to press ahead with the military operation until the IS and Kurdish Syrian fighters no longer pose a security threat to Ankara. It was the first U.S. criticism of its NATO ally since it launched a U.S.-backed incursion into northern Syria to help Syrian rebels seize the town of Jarablus from the Islamic State group. They have been clashing with Kurdish Syrian forces around the town to try to...