British Defense Secretary Ben Wallace said Moscow must respect international airspace after the US accused the Russian Air Force of shooting down a US drone in the Black Sea.

Mr Wallace made the statement to Reuters news agency on the sidelines of an exhibition in Chiba, near Tokyo.

The US military said yesterday that it was forced to drop a UAV into the sea after a Russian fighter intercepted it and damaged the propeller.

According to the US military’s European command, the incident, which happened at 08:03 yesterday, was the result of an “unsafe and unprofessional interception” by a Russian fighter. The State Department summoned the Russian ambassador to Washington, Anatoly Antonov, and presented him with a protest over the incident.

In Moscow, the Ministry of Defense rejected the American version of events. It said the UAV crashed in the Black Sea, near the Crimean peninsula, due to a sharp maneuver and that it was never hit by a Russian fighter.

He clarified that fighters were sent to identify an unknown intruder who was threatening to violate Russian airspace. The Russian jets did not use their weapons and did not come into contact with the unmanned aerial vehicle, returning safely to their base, the Defense Ministry said in a statement.

Instead, the US military’s European command said a Russian Sukhoi Su-27 fighter jet flew in front of the UAV and deliberately spilled fuel on it, before knocking out its propeller. Pentagon spokesman Pat Ryder said that since it was no longer possible to maneuver, it was decided to dive into the Black Sea. He estimated that one Russian fighter was also damaged and that the interception took 30 to 40 minutes.

Aircraft of the MQ-9 type are primarily used for reconnaissance, but can also carry weapons and have countermeasures as well. They have sensors capable of covering vast areas.

The US Pentagon has not specified, at least so far, what the mission of the UAV was, nor whether it was armed.