Turkish troops and allied Syrian rebels have driven the Islamic State group from the last strip of territory it controlled along the Syrian-Turkish border, a Turkish news agency reported.
The advance effectively seals the extremist group's self-styled caliphate off from the outside world, shutting down key supply lines used to bring in foreign fighters, weapons and ammunition.
The Anadolu news agency reported on Sunday that Turkey-backed Free Syrian Army rebels have cleared the area between the northern Syrian towns of Azaz and Jarablus.
It said the advance "has removed terror organisation Daesh's physical contact with the Turkish border in northern Syria".
Daesh is an Arabic acronym for the Islamic State group.
Turkey has launched two incursions into Syria since August 24 in an operation designed to drive IS away from the border and prevent the advance of US-backed Kurdish forces, which are also battling the extremist group.