The US Air Force has released video said to show a Russian jet intercepting an American drone and dumping fuel in its path over the Black Sea.

The US military said two Russian Su-27 jets intercepted the unmanned MQ-9 Reaper in international airspace on Tuesday before one hit its propeller, forcing US forces to bring it down.

It said the fuel dump was likely done to damage the drone and said the Russian aircraft flew in “a reckless, environmentally unsound and unprofessional manner”.

Russia’s defence ministry said the jets did not come into contact with the drone and claimed it crashed due to “sharp manoeuvring”.

It said the aircraft was flying towards the Russian border with its transponders – wireless communication devices – turned off.

The incident has demonstrated the increasing risk of a direct confrontation between the two superpowers because of the Ukraine war.