British Air Force Typhoon FGR4s have conducted a mission with French warplanes in a combined operation targeting an underground arms cache in Syria employed by the IS group, as stated by the UK's MoD.
The location, pinpointed through reconnaissance, was believed to be storing arms and explosives, the statement said, and was located in mountains just north of the ancient city of Palmyra in the heart of Syria.
"The RAF jets used precision-guided Paveway IV munitions to hit a several entry passages down to the facility... preliminary assessments are that the target was engaged successfully," the MoD said.
There was no indication of any harm to civilians in the attack conducted Saturday night and every plane involved made a safe return, the ministry further stated.
The Typhoon FGR4s were backed up by a Voyager refuelling tanker.
IS - referred to as ISIS - enforced extremist governance over parts of both Syria and Iraq before its territorial defeat in 2019.
"This operation shows our UK leadership, and commitment to stand shoulder to shoulder with our partners, to eradicate any resurgence of the terrorist group and their violent and radical beliefs in the area," the British Defence Secretary John Healey stated.
RAF aircraft have carried out surveillance missions over Syrian airspace to "prevent any efforts to regroup" of Islamic State following its routing at the climactic battle in Baghuz in 2019, the authorities noted.
"I extend gratitude to all the members of the UK armed forces who took part in this operation for their skill and their valour," the Defence Secretary added. "They were part of numerous British personnel deployed over the festive period. This operation, to remove dangerous terrorists who pose a risk to our security, demonstrates how our armed forces are always on standby, throughout the year, protecting the UK domestically and influential overseas."
In December, the US military carried out what it called a "large-scale strike" against IS targets in Syria, subsequent to an attack killed two American soldiers and a civilian interpreter in the Palmyra area.
The UN says Islamic State still maintains an estimated 5,000 to 7,000 militants in Syria and Iraq.
