Syrian opposition fighters began preparations to seize Aleppo a year ago, but the operation was delayed by war in Gaza and ultimately launched last week when a ceasefire took hold in Lebanon, the head of Syria's main opposition abroad told Reuters.
The factions were able to seize the city and parts of neighboring Idlib province so quickly in part because Hezbollah and other Iran-backed fighters were distracted by their conflict with Israel, Hadi al-Bahra said in an interview on Monday.
The Turkish military, which is allied with some of the opposition and has bases across its southern border in Syria, had heard of the armed groups' plans but made clear it would play no direct role, he added.
The assault in northwestern Syria was launched last Wednesday, the day that Israel and Lebanese armed group Hezbollah began a truce ending more than a year of fighting.
"A year ago they started really training and mobilizing and taking it more seriously," said Bahra, president of the National Coalition of Syrian Revolution and Opposition Forces, the internationally-recognized Syrian opposition.
"But the war on Gaza ... then the war in Lebanon delayed it. They felt it wouldn't look good having the war in Lebanon at the same time they were fighting in Syria," he said in his Istanbul office, in the first public comments on the fighters’ preparations by an opposition figure.
"So the moment there was a ceasefire in Lebanon, they found that opportunity ... to start."
The opposition operation is the boldest advance and biggest challenge to Syrian President Bashar al-Assad in years in a civil war where front lines had largely been frozen since 2020.
Syrian and allied Russian forces have launched counter attacks, which Bahra said are "destabilizing" Aleppo and Idlib and pose the biggest risk to civilians, given the earlier opposition advances had sought carefully to avoid such casualties.
IRAN, RUSSIA
The opposition retaking of Aleppo also paves the way for hundreds of thousands of Syrians displaced elsewhere in the country and in Türkiye to return home, Bahra said.
"Due to the Lebanese war and decrease in Hezbollah forces, (Assad's) regime has less support," he said, adding Iranian militias also have less resources while Russia is giving less air cover due to its "Ukraine problem".
Damascus, which is also backed by Iran, did not immediately comment on whether the opposition sought to avoid casualties and whether it risks destabilizing the region with air raids. Assad has vowed to crush the fighters and has launched air raids.
Iran-backed Hezbollah did not immediately comment on whether its war with Israel opened the door to Syrian opposition advances in Aleppo, where it also has personnel.
Tehran has pledged to aid the Syrian government and on Monday hundreds of fighters from Iran-backed Iraqi militias crossed into Syria to help fight the factions, Syrian and Iraqi sources said.
A Turkish defense ministry official said last week that Ankara was closely monitoring the mobilization and taking precautions for its troops.
The opposition fighters are a coalition of Türkiye-backed mainstream secular armed groups spearheaded by the Hayat Tahrir al-Sham group that has been designated a terrorist outfit by Türkiye, the US, Russia and other states.
Bahra's coalition, which does not include HTS, represents anti-Assad groups including the Türkiye-backed Syrian National Army or Free Syrian Army, which took territory north of Idlib over the last week.
It holds regular diplomatic talks with the United Nations and several states.
