However, much has changed in the years since Putin's intervention in Syria's civil war. The Russian president's invasion of Ukraine is nearly three years old, and Israel's war against Hamas, as well as its targeting of Hezbollah and Assad's ally Iran, adds to the complications.

The rebel coalition consists of "well-established armed Islamist factions who, despite their differences, are united in fighting Assad and Iran-backed militias", said CNN. But the driving force behind the fighting is Hayat Tahrir al-Sham (HTS), a "formidable" and controversial Islamic faction that has deep roots in Syria's ongoing civil war.

In just a few days, a patchwork of rebel forces has seized control of a broad stretch of land in the west and northwest of Syria. But it’s unclear just how much support Syria’s weakened allies can provide.

The sources told Reuters that Hezbollah had not yet been asked to intervene, adding that the group was not ready to send forces to Syria at this stage following more than a year o