U.S. warplanes over Syria now routinely encounter Russian aircraft flying across the same battle space, a defense official said Tuesday.
"It's happened several times ... it's not really a daily thing," Army Col. Steve Warren, a spokesman for Operation Inherent Resolve, told Pentagon reporters in a briefing from Baghdad.
The most recent encounter was Saturday, when "a couple of Russian aircraft came within visual recognition distance of a couple of coalition aircraft," Warren said.
"Visual identification took place. All pilots conducted themselves appropriately and everyone went about their business," he said, adding that the two aircraft did not get closer than several miles apart.
"But it is dangerous … if two sets of aircraft come into the same piece of airspace without very clear, laid-out protocols for the safety of all involved," Warren said.
Two weeks after the Russian air force began bombing targets in Syria, the U.S. and its former Cold War-era adversary have no direct operations-level lines of communication for deconflicting the overlapping operations.
On Saturday, Pentagon officials held a 90-minute video conference with their counterparts in the Russian Ministry of Defense to discuss "steps that can be taken" by the two sides "to promote safe flight operations over Syria," Defense Department spokesman Peter Cook said.
It was the second such discussion since the U.S. and Russia resumed a military-to-military relationship in September.
A third secure video conference is scheduled for Wednesday.
"The focus of these discussions is on specific safety protocols for aircrews flying over Syria. Those discussions are progressing, but nothing has been finalized," Cook said.
The U.S. opposes the Russian airstrikes that are supporting ground forces loyal to Syrian leader Bashar al Assad. The U.S. opposes Assad and says his removal is key to any resolution to the civil war that is now in its fifth year.
Since the start of the Russian air campaign on Sept. 30, Russian aircraft have conducted about 80 strikes. Russia claims to be targeting Islamic State militants, but Warren said "only a fraction of those strikes" have hit areas controlled by the militants.
That puts the Russians and the U.S. on opposing sides of the multi-polar civil war as some of the rebel groups Russia is targeting are U.S. allies fighting the Islamic State.
The Russian operations are calling into question U.S. control of the airspace over Syria. Last week, a U.S. aircraft spotted a Russian warplane and changed its flight path to avoid an unsafe or potentially hostile encounter.
"To my knowledge, there's only been one incident or one case where coalition pilots changed course and decided to approach a bombing run from a different direction simply because ... there were Russian aircraft operating nearby," Warren said.
So far, the Russians appear to be more aggressive in approaching unmanned aircraft.
"It's happened more with our drones," Warren said. "We've seen instances where the Russians are — maybe they're flying a pattern of combat air patrols somewhere where one of our drones ... or one of our UAVs will sort of come nearby and the Russian will break his pattern and come over and take a close look at the drone."
Andrew Tilghman is the executive editor for Military Times. He is a former Military Times Pentagon reporter and served as a Middle East correspondent for the Stars and Stripes. Before covering the military, he worked as a reporter for the Houston Chronicle in Texas, the Albany Times Union in New York and The Associated Press in Milwaukee.