The men, who had been operating a reconnaissance drone, spotted a wide, thin disc hovering in the distance.
It's certainly not surprising to see aircraft in the skies over Ukraine these days, but this particular video - which has been doing the rounds on social media this week - shows no ordinary aircraft.
The footage was filmed by soldiers from the 406th Battalion in the Ukraine Armed Forces (UAF) through the thermal camera of a DJI brand Mavic 3T quadcopter reconnaissance drone.
In the background, the men can be heard discussing the object.
"I'm telling you, it's a UFO, it's standing still," one of them says.
"Zoom in more, it's standing still. Do you see ?"
"Can't see anything on the thermal cameras - maybe ram it ?"
As things stand, it remains unclear exactly where the footage was captured or what the object could be.
Some online sleuths have suggested that it could be a fata morgana - a type of optical illusion that causes objects on the ground or ocean to appear to be floating in the sky.
You can check out the clip for yourself below - what do you think it shows?