BEIRUT (Reuters) - Hundreds of Syrian rebels are preparing to launch an operation to capture a town held by Islamic State at the border with Turkey, a senior Syrian rebel said on Sunday, a move that would frustrate Kurdish hopes to expand further in that area.
The rebels, Turkey-backed groups fighting under the banner of the Free Syrian Army, are expected to assault Jarablus from inside Turkey in the next few days, said the rebel official, who is familiar with the plans but declined to be identified.
"The factions are gathering in an area near the border (inside Turkey)," the rebel said.
Jarablus, located on the western bank of the Euphrates river, is the last significant town held by the militant Islamist group on Syria's border with Turkey. It is 34 miles (54km) east of al-Rai, a border town the same rebel groups recently took from Islamic State.
By taking Jarablus themselves, the rebel groups would preclude an assault on the town by the Syrian Democratic Forces (SDF), a group of Kurdish-dominated militias who on Aug. 6 took the city of Manbij, 20 miles (30km) to the south, from IS.
Turkey, an important supporter of the FSA groups, is worried that Kurds are using the SDF's westwards expansion against IS to extend their influence across northern Syria. The SDF already holds the eastern bank of the Euphrates opposite Jarablus.
On Saturday Turkish Prime Minister Binali Yildirim said that Ankara would play a more active role in addressing the conflict in Syria in the coming six months to stop it being torn along ethnic lines.
Islamic State has pulled personnel out of Jarablus in recent days, the rebel leader said. On Friday families of IS fighters were evacuated from Jarablus and another city nearby, al-Bab, to the group's stronghold of Raqqa, a war monitor said.
The operation aimed to effectively end Islamic State's foothold at the Turkish border, the official said, adding that the assault on the town would difficult.
"There will certainly be resistance. They will have mined it heavily," he said. "The operation of entering Jarablus will not be easy".
(Reporting by Tom Perry; Editing by Dominic Evans)