Al-Zoubi described the militant advance as an unexpected turn of events that could signal either a weakness in the Syrian army or highly trained factions executing a strategic surprise.

The offensive, led by Hayat Tahrir al-Sham (HTS) – including Al-Qaeda's former Syria branch, Jabhat al-Nusra – and allied factions, has raised questions about their backers and motivations as they make significant territorial gains in northwest Syria, entering Syria's second-largest city Aleppo for the first time since 2016.

The former Al-Qaeda affiliate and allied factions announced they had gained control of key locations in the shock offensive, such as the Aleppo Citadel and Saadallah al-Jabri Square.

The Syrian military, in response, has shut down main roads leading into Aleppo and instructed troops to follow "safe withdrawal" procedures from areas overrun by militants, three army sources told Reuters.

Sources added that civilian movement has also been restricted, with only military vehicles permitted through the checkpoints.

Another military source noted that the airport in Aleppo had been closed, and all flights have been cancelled as the situation has escalated.

With Russian air support now limited due to concerns over civilian casualties in urban areas, Al-Zoubi said the situation has become increasingly difficult for Syrian forces.

"The factions are spread out and move quickly," he said, pointing to the difficulty of pinpointing their locations for airstrikes. Nonetheless, Russian warplanes did target militant positions in Aleppo overnight, marking the first such raids since 2016, according to the Syrian Observatory for Human Rights.

Meanwhile, two military sources told Reuters that new Russian military aid is expected to arrive at the Russian-operated Hmeimim airbase, southeast of Latakia, within 72 hours.

The death toll in the recent clashes has now reached 311, including 183 militants, 100 Syrian soldiers, and 28 civilians.

Al-Zoubi downplayed concerns over the militants' control of the M5 highway between Aleppo and Damascus, suggesting that the Syrian army has other ways to circumvent the key route.

The sudden escalation in Aleppo coincided with a fragile ceasefire in Lebanon following a two-month Israeli assault and a yearlong war with Hezbollah. Al-Zoubi attributed the launch of the militants' offensive to mounting pressure from Syrian government forces, which have increasingly targeted these factions.

He also highlighted that the Syrian army has been building up reinforcements for over a year, alongside discussions about potential operations in Idlib, including the possibility of seizing control of the region.

In what appears to be a preemptive strike, the battle for Aleppo marks a significant shift in Syria's ongoing conflict. Islamist militant factions, led by Hayat Tahrir al-Sham, are making rapid territorial gains while government forces struggle to hold strategic positions.