British Air Force Typhoon jets have conducted a mission with France's air force in a combined operation targeting an underground arms cache in Syrian territory used by the IS group, according to the UK's MoD.
The site, identified by intelligence, was thought to be housing weapons and explosive materials, the statement said, and was located in mountains just north of Palmyra in Syria's central region.
"The RAF jets used Paveway IV guided bombs to target a several access tunnels leading to the site... preliminary assessments indicate the strike was effective," officials stated.
There was no evidence of any harm to civilians in the attack on Saturday evening and each participating jet returned to base without incident, the ministry further stated.
The British jets were supported by a Voyager refuelling tanker.
IS - alternatively referred to as Daesh - imposed militant control over parts of Iraq and Syria before its territorial defeat in 2019.
"This strike shows British leadership, and resolve to work closely with our allies, to eliminate any resurgence of the terrorist group and their harmful and extremist ideologies in the area," Britain's Defence Chief the minister stated.
RAF aircraft have carried out surveillance missions over Syrian airspace to "deter any attempted resurgence" of IS after its routing at the battle of Baghuz in 2019, the MoD reported.
"I extend gratitude to the personnel of our armed forces who took part in this mission for their expertise and their bravery," he added. "They were part of numerous British troops on duty over Christmas and New Year. This mission, to eliminate terrorist threats who pose a risk to our safety, highlights how British military are prepared to act, continuously, ensuring Britain's security within its borders and powerful internationally."
Last December, the United States armed forces executed what it described as a "large-scale strike" on Islamic State objectives in Syria, subsequent to an assault resulted in the deaths of two US servicemembers and a civilian interpreter in Palmyra.
The United Nations estimates Daesh still has between 5,000 and 7,000 combatants in both countries.
