The United States Air Force (USAF) said that a number of small unidentified drones were detected around three airbases in the United Kingdom over the past week.

The US Air Forces in Europe said "small unmanned aerial systems" were seen over Royal Air Force (RAF) Lakenheath, RAF Mildenhall in Suffolk, and RAF Feltwell, in Norfolk, eastern England.

Unclear whether drones were hostile

The incidents took place between November 20 and 22 and it was not clear whether the drones had any hostile intent.

"The UASs were actively monitored and installation leaders determined that none of the incursions impacted base residents or critical infrastructure," the air force said.

"To protect operational security, we do not discuss our specific force protection measures but retain the right to protect the installation. We continue to monitor our airspace and are working with host-nation authorities and mission partners to ensure the safety of base personnel, facilities and assets."

Lakenheath houses the 48th Fighter Wing, which the USAF describes as the foundation of its combat capability in Europe.

Nearby Mildenhall hosts the 100th Air Refueling Wing while Feltwell is a hub for housing, schools and other services.

The sightings took place in the same week that Ukraine struck targets inside Russia with intermediate-range missiles supplied by the US and Britain after President Joe Biden and Prime Minister Keir Starmer authorized use of the weapons.

Russia retaliated by launching a new intermediate range ballistic missile at Ukraine.

President Vladimir Putin also said his country had the right to strike nations that allowed their weapons to be used against Russia.

kb/lo (dpa, AP)