British Air Force Typhoon jets have conducted a mission with French warplanes in a coordinated attack on an underground arms cache in Syrian territory operated by the IS group, as stated by the UK's MoD.
The site, located using reconnaissance, was thought to be storing arms and explosives, the release indicated, and was located in mountains just above the ancient city of Palmyra in central Syria.
"Our aircraft used Paveway IV guided bombs to target a number of approach shafts leading to the site... early reports indicate the target was engaged successfully," the ministry announced.
There was no evidence of any civilian casualties in the attack on Saturday evening and every plane involved returned to base without incident, the MoD added.
The Typhoon fighters were assisted by a Voyager tanker plane.
The Islamic State group - also known as ISIS - enforced jihadist rule over large swathes of both Syria and Iraq until 2019.
"This action underscores the UK's leading role, and commitment to work closely with allied nations, to eliminate any revival of Daesh and their dangerous and violent ideologies in the Middle East," Britain's Defence Chief John Healey said.
British military aircraft have carried out patrols over Syria to "prevent any attempted comeback" of IS following its routing at the climactic battle in Baghuz in the year 2019, the ministry said.
"I must thank the personnel of our armed forces participating in this strike for their skill and their valour," Healey added. "They were part of numerous UK service members deployed over Christmas and New Year. This action, to eliminate dangerous terrorists who endanger our security, shows how our armed forces are always on standby, all year round, protecting the UK at home and influential overseas."
During December, the American forces carried out what it termed a "large-scale strike" targeting Daesh sites in the country, following an ambush killed two American soldiers and a civilian interpreter in Palmyra.
The UN says Islamic State still maintains an estimated 5,000 to 7,000 fighters in Syria and Iraq.
