After 13 years of civil war, Syria's opposition militias sensed an opportunity to loosen President Bashar al-Assad's grip on power when, about six months ago, they communicated to Turkiye plans for a major offensive and felt they had received its tacit approval, two sources with knowledge of the planning said.
Launched barely two weeks ago, the operation's speedy success in achieving its initial goal — seizing Syria's second city, Aleppo — took almost everybody by surprise. From there, in a little more than a week, the rebel alliance reached Damascus and on Sunday, put an end to five decades of Assad family rule.
The lightning advance relied on an almost perfect alignment of stars for the forces opposed to Assad: his army was demoralised and exhausted; his main allies, Iran and Lebanon's Hizbollah, were severely weakened by conflict with Israel; and his other key military supporter, Russia, was distracted and losing interest.
There was no way the rebels could go ahead without first notifying Turkiye, which has been a main backer of the Syrian opposition from the war's earliest days, said the sources, a diplomat in the region and a member of the Syrian opposition.
Turkiye has troops on the ground in northwest Syria, and provides support to some of the rebels who were intending to take part, including the Syrian National Army (SNA) — though it considers the main faction in the alliance, Hayat Tahrir al-Sham (HTS), to be a terror group. The rebels' bold plan was the brainchild of HTS and its leader Ahmed al-Sharaa, better known as Abu Mohammed al-Golani, the diplomat said.
Because of his former ties to al Qaeda, Golani is designated as a terrorist by Washington, Europe and Turkiye. However, over the past decade, HTS, previously known as the Nusra Front, has tried to moderate its image, while running a quasi-state centred on Idlib, where, experts say, it levied taxes on commercial activities and the population.
Turkish President Tayyip Erdogan's government, which struck a deal with Russia in 2020 to de-escalate fighting in northwestern Syria, has long opposed such a major rebel offensive, fearing it would lead to a new wave of refugees crossing its border.
However, the rebels sensed a stiffening of Ankara's stance towards Assad earlier this year, the sources said, after he rebuffed repeated overtures from Erdogan aimed at advancing a political solution to the military stalemate, which has left Syria divided between the government and a patchwork of rebel groups with an array of foreign backers.
The Syrian opposition source said the rebels had shown Turkey details of the planning, after Ankara's attempts to engage Assad had failed.
The message was: "That other path hasn't worked for years — so try ours. You don't have to do anything, just don't intervene."
Reuters was unable to determine the exact nature of the communications.
Hadi Al-Bahra, head of the internationally recognised Syrian opposition abroad, told Reuters last week that HTS and SNA had had "limited" planning together ahead of the operation and agreed to "achieve cooperation and not clash with each other".
He added that Turkiye's military saw what the armed groups were doing and discussing.
Turkiye's foreign and defence ministries did not respond directly to Reuters questions about an HTS-Ankara understanding about the Aleppo operation. In reply to questions about Turkiye's awareness of battlefield preparations, a Turkish official told Reuters that the HTS "does not receive orders or direction from us (and) does not coordinate its operations with us either".
The official said "in that sense" it would not be correct to say that the operation in Aleppo was carried out with Turkiye's approval or green light. Turkish intelligence agency MIT did not immediately respond to a request for comment.
Reuters was unable to reach a representative for HTS.
VULNERABLE
The rebels struck when Assad was at his most vulnerable.
Distracted by wars elsewhere, his military allies Russia, Iran, and Lebanon's Hizbollah failed to mobilise the kind of decisive firepower that had propped him up for years.
Syria's weak armed forces were unable to resist. A government source told Reuters that tanks and planes were left with no fuel because of corruption and looting — an illustration of just how hollowed out the Syrian state had become.
Over the past two years, morale had severely eroded in the army, said the source, who requested anonymity because of fear of retribution.
Aron Lund, a fellow at Century International, a Middle-East focused think tank, said the HTS-led coalition was stronger and more coherent than any previous rebel force during the war, "and a lot of that is Abu Mohammed al-Golani's doing". But, he said, the Syrian army's weakness was the deciding factor.
"After they lost Aleppo like that, Syrian government forces never recovered and the more the rebels advanced, the weaker Assad's army got," he said.
The pace of the rebel advances, with Hama being captured on Dec 5 and Homs falling on or around Sunday at the same time government forces lost Damascus, exceeded expectations.
GAZA FALLOUT
Sources familiar with Hizbollah deployments said the Iran-backed group, which propped up Assad early in the war, had already withdrawn many of its elite fighters from Syria over the last year to support the group as it waged hostilities with Israel — a conflict that spilled over from the Gaza war.
The sources said Hizbollah did not want to engage in big battles in Syria as the group focused on starting a long road to recovery from heavy blows.
For the rebel alliance, the withdrawal of Hizbollah presented a valuable opportunity.
"We just wanted a fair fight between us and the government, " the Syrian opposition source said.
Assad's fall marks a major blow to Iranian influence in the Middle East, coming so swiftly after the killing of Hizbollah leader Hassan Nasrallah and the damage done by Israel to the group.
Turkiye, on the other hand, now appears to be Syria's most powerful external player, with troops on the ground and access to the rebel leaders.
"Turkiye is the biggest outside winner here. Erdogan turned out to be on the right — or at least winning — side of history here because his proxies in Syria won the day," said Birol Baskan, Turkey-based political scientist and former non-resident scholar at Middle East Institute.
* The writers are from Reuters