Washington has requested Moscow not to bomb areas of Northern Syria where US Special Forces are being deployed. These areas are under the jurisdiction of so-called “moderate opposition” rebels who are supported by the US and its allies.
The areas in question pertain to pockets of Northern Syria in which various US-NATO supported jihadist groups including the Islamic State (ISIS) and Al Nusrah are fighting Syrian government forces (SAA) and their allies. These terrorist pockets are protected by the US-led coalition and Turkey:
The Pentagon has asked Russia to stay away from parts of northern Syria where US special operations troops are training local fighters [i.e. terrorists including the Islamic State ] to combat the Islamic State group [the opposition rebels are allies of ISIS, ISIS is supported by the US and has special forces within its ranks], military officials said Thursday. The acknowledgement is significant because the Pentagon has repeatedly stressed it is not cooperating with Moscow as the two powers lead separate air campaigns in war-ravaged Syria…. (Al Monitor, AFP Report, February 18 2016)