Two rebel groups are leading the push. One is Hayat Tahrir al-Sham ( HTS ), which emerged from al-Qaeda’s Syrian affiliate. It cut ties with the jihadist group in 2017 and has since set up a provisional government in rebel-held Idlib province in north-west Syria. The other faction, the Syrian National Army ( SNA ), is a Turkish proxy.

For the first time since 2012, Assad is on his own. It took his forces four years to capture Aleppo – the rebels had taken it back within hours. Broaden your horizons with award-winning British journalism. Try The Telegraph free for 3 months with unlimited access to our award-winning website, exclusive app, money-saving offers and more.

Russia, Iran and Hezbollah, otherwise known as Bashar Assad’s lifeline in Syria, have bigger fish to fry at the moment.

Syrian rebels launched a surprise attack on Saturday and quickly advanced through several provinces in the north and northwest of Syria, including the city of Aleppo, the country’s second largest city.

Diminished support for the Syrian government from Iran, Hezbollah and Russia enabled opposition forces to take the initiative and seize new territory.

Rebels captured Syria's second-largest city, Aleppo, over the weekend and advanced toward Hama in a surprise incursion that reignited Syria's 13-year-old civil war and embarrassed President Bashar al-Assad's forces.

Syria carried out airstrikes targeting the rebel forces that seized the country's second largest city of Aleppo in a surprise advance last week that caught the government off guard.

Anti-government fighters are continuing to advance even as Syrian and Russian forces seek to halt their progress.