On Sunday, the al-Qaida linked Nusrah Front together with several armed rebel groups took over the city of Idlib, in the north of Syria.
The city, under government control, fell after last week rebel forces aligned with al-Nusra in a final bid to take the strategic city.
Syrian television claimed the Syrian army had not abandoned the city and instead had regrouped in southern areas to continue fighting.
However, it is the first time a new coalition based on Islamist armed rebel groups and the Nusrah Front, worked together against the government.
The gain follows an interview given during the weekend by Syrian President Bashar Assad accused the 60-country coalition fighting the Islamic State group of not wanting to end with the group entirely.
“They don’t want to get rid of ISIS (the Islamic State group) completely … There is no serious effort to fight terrorism, and what is being achieved by the Syrian forces on the ground equals in one day what is being achieved by these states in weeks,” said the head of State, during an interview with Russian media.
The new Islamist coalition involves the groups Ahrar al-Sham — largely funded by the Gulf States — , Jund al-Aqsa, Jaish al-Sunnah and Failaq al-Sham, all hardline jihadist groups that intend to impose Sharia law across Syria.
The Turkish government, which has provided support for armed rebel groups fighting Assad, greeted the takeover of the city.
"Of course Turkey is happy that Idlib is controlled by the opposition front and that Assad lost ground," said one official quoted by The Sydney Morning Herald.
Idlib, which is the size of Lebanon, is strategic since it’s located between the embattled city of Aleppo — where rebels and the Islamic State group are fighting the Syrian army — and Latakia, one of the most important government strongholds.