Royal Air Force Typhoon jets have joined forces with France's air force in a combined operation against an underground arms cache in Syria employed by the IS group, per a report from the British defence ministry.
The facility, located using reconnaissance, was assessed as storing arms and explosives, the announcement noted, and was located in mountains just to the north of Palmyra in central Syria.
"Our aircraft used laser-guided Paveway IV weapons to target a number of approach shafts leading to the site... early reports suggest the strike was effective," the MoD said.
There was no indication of any civilian casualties in the strike late on Saturday and each participating jet returned to base without incident, the MoD added.
The Typhoon fighters were backed up by a Voyager aerial refuelling aircraft.
IS - referred to as Daesh - enforced extremist governance over significant areas in Iraq and Syria before its territorial defeat in 2019.
"This operation demonstrates British leadership, and determination to work closely with our allies, to eliminate any resurgence of IS and their harmful and extremist ideologies in the region," the British Defence Secretary John Healey stated.
RAF aircraft have performed patrols over Syria to "prevent any efforts to regroup" of IS following its defeat at the battle of Baghuz in 2019, the ministry said.
"I must thank all the members of the UK armed forces involved in this strike for their expertise and their valour," Healey said. "Including them were a great many British personnel stationed over the festive period. This action, to remove militants who threaten our security, demonstrates how our armed forces are prepared to act, throughout the year, ensuring Britain's security within its borders and powerful internationally."
Last December, the US military carried out what it called a "massive strike" on IS targets in the country, after an attack resulted in the deaths of two US troops and a civilian linguist in Palmyra.
The U.N. estimates IS still boasts between 5,000 and 7,000 militants in both countries.
