RAF Typhoon jets have operated alongside France's air force in a coordinated attack against an underground arms cache in Syrian territory used by the Islamic State group (IS), according to the UK Ministry of Defence.
The facility, pinpointed through reconnaissance, was thought to be storing arms and explosives, the statement said, and was located in mountains just above Palmyra in the heart of Syria.
"Our fighter planes employed laser-guided Paveway IV weapons to hit a number of access tunnels providing entry to the site... early reports indicate the objective was successfully hit," the ministry announced.
There was no indication of any civilian impact in the operation on Saturday evening and all the aircraft made a safe return, the defence officials confirmed.
The Typhoon fighters were supported by a Voyager refuelling tanker.
The Islamic State group - alternatively referred to as the so-called Islamic State - enforced militant control over significant areas in both Syria and Iraq prior to its 2019 collapse.
"This action demonstrates British leadership, and resolve to stand shoulder to shoulder with allied nations, to stamp out any re-emergence of Daesh and their dangerous and violent ideologies in the region," UK Defence Secretary John Healey stated.
RAF aircraft have performed surveillance missions over Syria to "forestall any efforts to regroup" of Islamic State following its routing at the climactic battle in Baghuz in 2019, the ministry said.
"I want to thank every member of our armed forces participating in this mission for their professionalism and their courage," Healey added. "They were part of a great many British troops on duty over the holidays. This operation, to take out terrorist threats who threaten our security, demonstrates how UK forces are ready to step up, all year round, keeping Britain secure at home and influential overseas."
Last December, the US military executed what it called a "large-scale strike" on Daesh sites in Syria, after an attack claimed the lives of two US troops and a civilian linguist in Palmyra.
The U.N. reports Islamic State still boasts an estimated 5,000 to 7,000 militants in Iraq and Syria.
