The successful experience in Kobanî had informed U.S. policy in regard to arming Syrian opposition groups other than the Kurdish YPG, with plans to give other groups technicals equipped with radio and GPS equipment to call in airstrikes. John R. Allen, President Obama's envoy to the international coalition against ISIL, stated "It is clearly part of our plan, that not only we will train them, and we will equip them with the latest weapons systems, but we will also protect them when the time comes". In March 2015, the United Kingdom announced that it was sending around 75 military instructors to train Syrian opposition forces. The train-and-equip program started on 9 May 2015. On 25 May, Turkey and the U.S. agreed "in principle" on the necessity to support these forces with air support.