JARABLUS, Syria (Reuters) - Two months after driving Islamic State from this Syrian border town, the young rebel fighters patrolling its streets nurse an ambition beyond the aims of their Turkish backers: to break the siege of Aleppo.

Members of Turkish-backed Free Syrian Army (FSA) stand in front of a wall where a portrait of Turkish President Tayyip Erdogan is displayed in the border town of Jarablus, Syria, October 19, 2016. REUTERS/Umit Bektas

These Free Syrian Army (FSA) fighters, some in their teens, others hardened by years of war, swept into Jarablus almost unopposed in August.

They were part of Turkey’s “Operation Euphrates Shield” meant to clear the jihadists from the border and prevent Kurdish militias gaining ground in their wake.

But for them, that operation was a means to an end, just the start of a journey that would ultimately see them battle their main enemy - the Russian-backed forces of President Bashar al-Assad - and come to the aid of hundreds of thousands of civilians encircled in opposition-held eastern Aleppo.

Such ambitions leave Turkey in a difficult position as it restores relations with Moscow.

Long one of Assad’s fiercest opponents, Ankara’s main priority appears to have shifted towards preventing Kurdish territorial gains and away from pushing for his immediate departure, putting it at odds with the fighters it supports.

“Our most important target is to break the siege of Aleppo. There, our FSA brothers are trapped,” Ismail, a commander from the Sultan Murad group, an FSA faction, told Reuters in Jarablus, wearing camouflage fatigues and Adidas sneakers.

“This is our own idea, but in the coming days we will discuss this with our Turkish brothers,” he said.

The answer may not be what he wants to hear.

CO-FIGHTERS

Turkish President Tayyip Erdogan and Russia’s Vladimir Putin agreed at a meeting in Istanbul last week to try to seek common ground on Syria, despite backing opposing sides, although there has been little sign of concrete progress.

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Erdogan said he had spoken with Putin on Tuesday and agreed to try to help meet a Russian demand that fighters from the group formally known as the Nusra Front, now called Jabhat Fatah al Sham, be removed from Aleppo.

“The necessary orders were given to our friends, and they will do what is needed,” Erdogan said in a speech in Ankara.

Such willingness to do Moscow’s bidding is unlikely to go down well with the FSA fighters Turkey is backing.

“Russia says they are bombing terrorists, but be it al Nusra or Ahrar al Sham, these are people who have fought with us to save our land,” Sighli Sighli, another commander from the Sultan Murad brigade, told Reuters in Jarablus.

He said he was grateful for the backing of the Turkish military, and that the FSA’s recent advances could not have been achieved without it, but that Aleppo was the strategic goal.

“It’s not possible for us to accept what Russia or Iran or the PYD (Kurdish militia) wants to do with our country. This land belongs to Syrians, not Russians or Iranians,” he said.

HARDER FIGHT AHEAD

Some of the civilians in Jarablus, where shops have gradually reopened selling fruit and cloth as rebel fighters patrol the streets on foot and in pick-up trucks, are also suspicious of Ankara’s warming ties with Moscow.

“My family is starving in Aleppo. Thousands are starving... Erdogan has left our people there to die, he has abandoned us,” said one Turkmen resident who gave his name only as Yahya, and who said his wife and five children were in Aleppo.

“He sold Aleppo off to the Russians and Iranians. They made a deal and they no longer care about Aleppo,” he said, standing outside a grocery store in the main square.

Rebel fighters who have benefited from Turkish firepower in recent weeks are less skeptical, convinced that they will go on to battle Assad in Aleppo once Turkey’s ambition of flushing Islamic State from its border is achieved.

“We have put aside our desire to fight Assad just for now. We haven’t abandoned it ... it’s not like we’ve dropped our target,” Bessam Muhammed, a 40-year-old rebel fighter, told Reuters in the garden of a Turkish-run field hospital.

“We haven’t come all the way and fought this war to seize Jarablus and then stay here,” he said.

Operation Euphrates Shield has made good progress. Backed by Turkish tanks and warplanes, the rebels captured the village of Dabiq, southwest of Jarablus, from Islamic State on Sunday, a stronghold where the jihadist group had promised a final, apocalyptic battle with the West.

Turkey’s military has said border security has now been largely achieved. But as the offensive moves towards al-Bab, 35 km (22 miles) northeast of Aleppo, the battle may get harder.

“The fight here for Jarablus was easy, but the fight for al-Bab will be much harder. Here there wasn’t much resistance. They fled the town and we moved in,” said Mahmut, 26, an FSA fighter wearing a Turkish police helmet.

“We don’t want to stop here or in al Bab. Next is Aleppo.”