British Air Force Typhoon FGR4s have joined forces with French warplanes in a joint strike targeting an underground arms cache in Syrian territory used by the IS group, according to the UK's MoD.
The location, identified by intelligence, was thought to be housing weapons and explosive materials, the announcement noted, and was situated in hills just to the north of Palmyra in Syria's central region.
"Our fighter planes employed laser-guided Paveway IV weapons to target a number of access tunnels leading to the site... preliminary assessments are that the strike was effective," the MoD said.
There was no evidence of any civilian impact in the strike on Saturday evening and all the aircraft returned to base without incident, the MoD added.
The British jets were supported by a Voyager tanker plane.
IS - also known as ISIS - imposed militant control over significant areas in Iraq and Syria before its territorial defeat in 2019.
"This action underscores our UK leadership, and determination to work closely with our allies, to eradicate any re-emergence of Daesh and their violent and radical beliefs in the area," Britain's Defence Chief the minister stated.
British military aircraft have conducted surveillance missions over Syrian airspace to "prevent any efforts to regroup" of the group after its defeat at the climactic battle in Baghuz in 2019, the ministry said.
"I want to thank all the members of our armed forces involved in this strike for their expertise and their bravery," he added. "Including them were a great many British troops stationed over the holidays. This operation, to take out dangerous terrorists who endanger our safety, shows how our armed forces are prepared to act, continuously, keeping Britain secure within its borders and influential overseas."
In December, the American forces conducted what it called a "massive strike" against IS targets in Syria, after an assault claimed the lives of two US servicemembers and a local interpreter in the Palmyra area.
The UN says Islamic State still boasts between 5,000 and 7,000 fighters in Iraq and Syria.
