Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Turkey Threatens Attack on Syrian Kurds as US Envoy Holds Talks With Ankara Dorian Jones ISTANBUL - Tensions between the United States and Turkey are increasing as Washington's special representative for Syria engagement, Ambassador James Jeffrey, visits Ankara in a bid to iron out differences with its NATO ally. Ankara has threatened military action against Syrian Kurdish militia the YPG, unless the two countries agree on steps to distance the YPG from the Turkish border. The YPG is a key U.S. ally in the fight against Islamic State terrorists. Ankara, however, links the militia to the Kurdish rebel group, the PKK, which has been fighting a decades-long insurgency against Turkey. Turkish forces are continuing to mass on Syria's border, where the YPG is based.