British Air Force Typhoon FGR4s have conducted a mission with France's air force in a coordinated attack on an underground arms cache in Syrian territory operated by the IS group, according to the UK's MoD.
The facility, located using surveillance, was thought to be housing weapons and explosive materials, the statement said, and was situated in mountainous terrain just above Palmyra in the heart of Syria.
"The RAF jets used laser-guided Paveway IV weapons to strike a several entry passages down to the depot... initial indications indicate the strike was effective," the MoD said.
There was no sign of any civilian impact in the strike conducted Saturday night and every plane involved made a safe return, the defence officials confirmed.
The Typhoon FGR4s were backed up by a Voyager aerial refuelling aircraft.
The Islamic State group - referred to as Daesh - enforced extremist governance over parts of Iraq and Syria prior to its 2019 collapse.
"This operation underscores British leadership, and resolve to work closely with allied nations, to eliminate any resurgence of Daesh and their dangerous and violent ideologies in the region," Britain's Defence Chief the Defence Secretary stated.
RAF aircraft have performed overwatch operations over Syria to "prevent any attempted comeback" of Islamic State following its military defeat at the battle of Baghuz in 2019, the ministry said.
"I want to thank every member of British forces who took part in this strike for their professionalism and their courage," Healey added. "They were among numerous British personnel stationed over the festive period. This mission, to take out terrorist threats who endanger our security, highlights how UK forces are prepared to act, continuously, keeping Britain secure at home and strong abroad."
In December, the US military conducted what it called a "major assault" against IS targets in the country, following an assault killed two US troops and a local interpreter in the Palmyra area.
The U.N. reports Islamic State still boasts between 5,000 and 7,000 combatants in Syria and Iraq.
