A pro-Turkey rebel group on Sunday began withdrawing its forces and heavy weapons from parts of northern Syria under a deal brokered by Ankara and Moscow to avert a Russian-backed Syrian army offensive on what is the country's last major opposition stronghold, according to a group monitoring the conflict.

The Failaq al-Sham group "began pulling out of areas in the southern countryside of Aleppo and the western suburbs of Aleppo city with heavy weapons, including tanks and cannon," the Britain-based Syrian Observatory for Human Rights said.

It said the group had some 8,500 to 10,000 fighters and was the third largest among those operating in the region. The biggest jihadi group, Hayat Tahrir al-Sham (HTS), which controls 60 percent of Idlib, has yet to say whether it will stage a pullout under the deal, which Turkish President Recep Tayyip Erdogan has said would "prevent a humanitarian crisis."

Failaq al-Sham forms part of a Turkish-backed alliance known as the National Liberation Front (NLF), which was formed in August to counter HTS, the monitor said.

Reports 'a lie'

But on Sunday night, a leader of the group told Reuters news agency that the report was false.

"What was cited of our withdrawal from the demilitarized zone is a lie," said Sheikh Omar Huziefa. Another NLF commander, Abdul Salam Abdul Razzak, said there was no change in the situation on the ground.

Reports either way could so far not be independently verified.

Read more: Idlib crisis averted, but Syrian refugees still 'struggling for their survival'

Fears of large-scale assault

The deal between Russia and Turkey foresees setting up a new demilitarized zone in Idlib province by October 15 that will be patrolled by Turkish and Russian forces.

Russian-backed Syrian troops have built up a large presence around Idlib province over the past weeks, leading to concerns that an offensive on the opposition stronghold could be imminent. The UN has warned that such an attack on Idlib could result in a humanitarian catastrophe.

Syria's seven-year civil war, which began after a brutal government crackdown on initially peaceful anti-government protests, has since grown into a complex conflict involving numerous militant groups pursuing a variety of interests. The war has claimed hundreds of thousands of lives and led to millions fleeing their homes.

Read more: Demilitarized zone in Syria's Idlib: What comes next? 

tj/kms (Reuters, AFP)

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