"As far as calls to keep [aircraft] deconflicted…my understanding is that this is a routine thing and they do them on a daily basis," Dorrian said at a briefing.
Earlier this month, the US Department of State announced it was temporarily closing bilateral channels with Russia that had been established to sustain a ceasefire in Syria.
Russia conducted an aerial campaign in Syria from September 2015 until mid-March of this year, when President Vladimir Putin withdrew most Russian forces, saying they had accomplished their objectives in Syria.
Inherent Resolve, a US-led coalition of more than 60 nations, has been carrying out airstrikes against the Islamic State terror group in Syria since September 2014, but without the approval of Syria’s government or the United Nations Security Council.