A major attack by opponents of President Bashar al-Assad has seen militants advance deep into Aleppo, forcing the Syrian army to redeploy its forces, Reuters reported, citing sources in the Syrian Arab Army (SAA) command.

The command acknowledged the loss of control over a large part of Aleppo, which had been under official control since 2016. The attack resulted in serious losses among the Syrian military: dozens of soldiers were killed, making this offensive one of the most destructive in recent years.

The militants also captured the strategic town of Maaret al-Numan in Idlib province, in what rebel sources told Reuters was part of a wider campaign to weaken the SAA's position in the country's northwestern provinces.

Analysts say the loss of Aleppo, Syria's largest city, could dramatically change the balance of power in the region. Despite Russia and Iran's efforts to support the Syrian army, its ability to hold key areas is in serious question. The militants' advance in Aleppo and neighboring provinces threatens further destabilization and complicates the prospects for restoring the country's territorial integrity.