By Natasha Bertrand, Business Insider–

A cease-fire agreement aimed at stopping the battle for Syria’s largest city long enough to evacuate civilians and rebel fighters has already collapsed, less than one full day after it was brokered in Ankara, Turkey, by Russian and Turkish officials.

It is unclear who broke the truce first. Moscow, which backs Syrian President Bashar Assad, accused the rebels of rupturing the fragile peace, while the opposition said pro-Assad Shiite militias resumed their attacks on besieged districts of eastern Aleppo early Wednesday morning.

The militias, which are backed by Iran, halted the evacuation of the first group of civilians, a source within the opposition told Business Insider on Wednesday. The source said the militias demanded that injured Shiites in the villages of Foua and Kafraya in the rebel-held Idlib province — where the rebels and civilians were to be sent — be evacuated first.

The source said Iran had expressed fears that the Shiites would face retribution if Sunni Arab rebels were allowed to leave eastern Aleppo. But Osama Abo Zaid, a legal adviser to Aleppo’s rebel groups, said Iran was being motivated by “exclusively sectarian and crippling” considerations.

“This is a total catastrophe,” said Ammar Abogoda, the head of the Aleppo-based news channel Aleppo Today who also goes by Hakeem Haladi.

“The shelling has started heavily again, airplanes are in the sky dropping cluster bombs,” he said via WhatsApp on Wednesday. “Russia and Syria signed on to the deal and it’s collapsed now — all because of Iran.”

“How on earth can we tell the American people that Iran is playing this game under the watch of our government?” Abogada, who is not in Aleppo but travels there regularly, said. “It’s a total disaster. I can’t even describe the situation down there.”

Iran, a staunch ally of Assad that arms and funds the Shiite militias fighting on his behalf, reportedly felt blindsided by the terms of the truce brokered in Turkey between Russia and the rebels.

“Iran considers the Russian deal with opposition, facilitated by Turkey, a deal made without their knowledge and intended to sideline Iran,” Syrian journalist Hadi Alabdallah tweeted Wednesday. “For this reason, Iran-backed militias

[have] obstructed the evacuation of the injured since yesterday until now, highlighting Russia-Iran discord over Syria.”

aleppo syriaBuses waiting to evacuate people from a rebel pocket in Aleppo, Syria, on Wednesday. Omar Sanadiki/Reuters

Further complicating the negotiations is the feeling that Russia, which turned the tide of the war when it launched an air campaign on behalf of Assad in October 2015, is quickly losing influence over Iran and the Assad regime itself — especially given the regime forces’ broadly successful ground invasion of eastern Aleppo over the past month.

Russia has been trying to persuade the Assad regime to accept the conditions of the truce, a spokesman for the Aleppo-based rebel group Noureddine Zinki told The Guardian on Wednesday. But Iran, whose proxy militias wield considerable power on the ground in Aleppo, was unwilling to accept the terms of the deal, said Asaad Hanna, a political officer in the opposition Free Syrian Army.

“The Iranians have so far refused to accept the outcome of the talks, even as Russia accepted many requests made by the opposition,” Hanna told Business Insider on Wednesday.

“Because the Russians don’t have fighters in Aleppo, like the Iranians do through their proxies, they cannot apply the cease-fire deal on the ground, in practice,” he added. “They have to deal with the Iranians because it’s their militias who are controlling the checkpoints and largely directing the pro-Assad forces in Aleppo.”

Syria Army Soldiers Flag Aleppo MosqueForces loyal to Syrian President Bashar Assad inside the Umayyad mosque, in the government-controlled area of Aleppo, during a media tour on Tuesday. REUTERS/Omar Sanadiki

The opposition is still negotiating with the Russians in Ankara, Hanna said, but would not meet with the Iranians directly. Iran’s foreign minister, Javad Zarif, will meet with his Turkish and Russian counterparts in Ankara on Wednesday, however, to discuss the terms of the truce, according to Reuters.

Russia and Iran, both staunch allies of Assad, have broadly been on the same page in Syria throughout the war. Russia reportedly intervened in the conflict at the request of Iranian Gen. Qassem Soleimani, who visited Russian President Vladimir Putin in August 2015 to request Russia’s help in bolstering Assad.

The newly fortified Russian-Iranian military alliance gave Putin more leverage and influence in the region in the short term and was therefore as beneficial to Moscow as it was to Tehran.

Now that Assad has essentially won his biggest victory of the more than five-year civil war, however, and is in control of Syria’s major urban areas, he and his Iranian allies may not feel as indebted to — or dependent on — Russian airpower.

AleppoForces loyal to Assad inside Aleppo’s historic citadel during a media tour on Tuesday. REUTERS/Omar Sanadiki

Still, Cliff Kupchan, an expert on Russia and Iran at the political risk firm Eurasia Group, said that tension between Russia and Iran should not be overstated and that it was most likely as much the Russians’ fault as it was the Iranians’ that the evacuation deal had not been implemented.

“The deal will be implemented at some point,” Kupchan said. “But before they follow through on it, the Russians and Iranians are trying to maximize their leverage and concessions from the armed rebels. They’re trying to see the rebels leave in as few numbers, and with the least amount of weapons, possible.”

Indeed, Turkey’s foreign minister, Mevlut Cavusoglu, told reporters on Wednesday from Ankara that “Russia, Iran, forces supported by Iran, and the regime” were “trying to obstruct” the deal.

aleppoAleppo seen from a government-controlled area on December 6. Reuters/Omar Sanadiki

Chris Kozak, a research analyst focusing on Syria at the Institute for the Study of War, said that while the breakdown of the evacuation deal “does highlight the strategic divergences that exist between Iran and Russia,” he didn’t think the differences were as severe as many assume.

“Iran likely aims to have a seat at the table in the final resolution of Aleppo City more broadly given its contributions (in the forms of advisors and manpower) to the fight,” Kozak said, “and may have decided to play spoiler in order to insert its interests into the bilateral negotiations between Russia and Turkey.”

But at the end of the day, Kozak stressed, pro-government forces, including Russia and Iran, remain united behind their interest in preserving the Assad regime — “despite some divergences on the interim military and political priorities on the ground.”

The US has been shut out of the Ankara talks, but the State Department said Wednesday it was aware of reports that implementation of the cease-fire and evacuation plan had failed “due to intense shelling on civilian neighborhoods in east Aleppo.”

“We urge all parties involved to get a cessation of hostilities back on track, permit departures for all those who want to leave the city, and allow deliveries of humanitarian assistance to all in need,” a State Department official told Business Insider on Wednesday.

“We strongly urge Russia, the Syrian regime, and Iran allow for UN monitoring as a safeguard against further atrocities,” the official said. “The world is watching.”