RAF Typhoon jets have joined forces with French warplanes in a coordinated attack targeting an hidden munitions depot in Syrian territory employed by the IS group, according to the British defence ministry.
The facility, identified by intelligence, was thought to be containing munitions and bombs, the statement said, and was located in mountains just north of the ancient city of Palmyra in central Syria.
"Our fighter planes utilized precision-guided Paveway IV munitions to strike a several access tunnels down to the site... preliminary assessments indicate the strike was effective," the MoD said.
There was no evidence of any civilian impact in the attack on Saturday evening and each participating jet returned safely, the MoD added.
The Typhoon FGR4s were supported by a Voyager aerial refuelling aircraft.
IS - referred to as the so-called Islamic State - established jihadist rule over significant areas in both Syria and Iraq until 2019.
"This operation shows our UK leadership, and resolve to work closely with our partners, to eradicate any resurgence of Daesh and their harmful and extremist ideologies in the area," UK Defence Secretary John Healey said.
RAF aircraft have carried out patrols over Syria to "deter any attempted resurgence" of Islamic State after its military defeat at the battle of Baghuz in 2019, the authorities noted.
"I extend gratitude to all the members of the UK armed forces who took part in this mission for their expertise and their bravery," the Defence Secretary said. "They were among thousands of British troops stationed over the festive period. This operation, to eliminate dangerous terrorists who endanger our safety, shows how our armed forces are ready to step up, all year round, keeping Britain secure domestically and strong abroad."
In December, the United States armed forces conducted what it termed a "large-scale strike" on Islamic State objectives in Syria, after an ambush killed two American soldiers and a local interpreter in the Palmyra area.
The UN says Islamic State still has an estimated 5,000 to 7,000 fighters in Syria and Iraq.
