Russia, one of Assad’s key allies, has promised Damascus extra military aid to thwart the rebels, two military sources said, adding new hardware would start arriving in the next 72 hours.

Robert Ford, who was the last US ambassador to Syria, said the attack showed that Syrian government forces are “extremely weak.” In some cases, he said, they appear to have “almost been routed.”

The offensive came as Iran-linked groups, primarily Lebanon’s Hezbollah, which has backed Syrian government forces since 2015, have been preoccupied with their own battles at home.

A ceasefire in Hezbollah’s two-month war with Israel took effect on Wednesday, the day the Syrian opposition factions announced their offensive. Israel has also escalated its attacks against Hezbollah and Iran-linked targets in Syria during the last 70 days.

Dareen Khalifa, a senior adviser with the International Crisis Group and an expert on Syrian groups, said the insurgents have signalled for a while that they were ready for an offensive. But no one expected the swift advance of the forces toward Aleppo.

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“It’s not only that the Russians are distracted and bogged down in Ukraine, but also the Iranians are distracted and bogged down elsewhere. Hezbollah’s distracted and bogged down elsewhere, and the regime is absolutely cornered,” she said. “But the surprise element comes in with how quickly the regime crumbled.”

The attack on Aleppo followed weeks of simmering low-level violence, including government attacks on opposition-held areas. Turkey, which has backed Syrian opposition groups, failed in its diplomatic efforts to prevent the government attacks, which were seen as a violation of a 2019 agreement sponsored by Russia, Turkey and Iran to freeze the line of the conflict.

Turkish security officials said on Thursday that Syrian opposition groups initially launched a long-planned “limited” offensive toward Aleppo, where attacks targeting civilians originated. However, the offensive expanded as Syrian government forces began retreating from their positions, the officials said.

The aim of the offensive was to reestablish the boundaries of the de-escalation zone, according to Turkish officials.

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The 2016 battle for Aleppo was a turning point in the war between Syrian government forces and rebel fighters after 2011 protests against Bashar al-Assad’s rule turned into an all-out war.

Russia and Iran and its allied groups helped Syrian government forces reclaim control of the city that year after a gruelling military campaign and a siege that lasted for weeks.

Besides backing opposition forces, Turkey has also established a military presence in Syria, sending troops into parts of the north-west. Separately and largely in the east of Syria, the United States has supported Syrian Kurdish forces fighting Islamic State militants.

The Syrian government did not comment on insurgents breaching Aleppo city limits.

The Kremlin said Friday that it considered the attack an encroachment on Syria’s sovereignty and that it supported the quickest possible establishment of constitutional order in the region.

“Of course, this is a violation of Syria’s sovereignty in this region,” Russian presidential spokesperson Dmitry Peskov told a press briefing.

Syria’s armed forces said in a statement Friday that they clashed with insurgents in the countryside around Aleppo and Idlib, destroying drones and heavy weaponry. They vowed to repel the attack and accused the insurgents of spreading false information about their advances.

The Syrian Observatory for Human Rights said the insurgents detonated two car bombs on Friday at the western edge of Aleppo. The war monitor said insurgents were also able to seize control of Saraqeb, south of Aleppo, a town at the strategic intersection of the highways linking Aleppo with Damascus and the coast. Syrian government authorities diverted traffic from that highway on Thursday.

An insurgent commander posted a recorded message on social media calling on Aleppo residents to co-operate with the advancing forces.

Turkey’s state-run Anadolu Agency reported that the insurgents entered the city centre on Friday and now control about 70 locations in the Aleppo and Idlib provinces.

Syria’s state media reported that projectiles from insurgents landed in student accommodations at Aleppo’s university in the city centre, killing four people, including two students.

AP, Reuters

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