The advance into Base 80, a large military position which militant groups have held since February, will help army troops move towards militants-held areas of Aleppo city and follow a string of successful offensives this month.

Militants from Liwa al-Tawid, the largest insurgent force in Aleppo, said that their unit as well as dozens of others had been pushed out of most parts of the base but were regrouping to retake the area, next to Aleppo International Airport, which is still under government control.

Militant groups said at least 25 of their members had killed during clashes.

The so-called Syrian Observatory for Human Rights said that hard-line militant groups linked to al Qaeda also took part in the clashes.

The militant groups captured the town of Safira, 20km (12 miles) south east of Aleppo, a week ago.

The army said at the time that Safira would be used to send in medicine and supplies to government-controlled areas of Aleppo, mired in a bloody stalemate for over a year. Its capture would have helped Friday's attack on Base 80, on the southeastern fringes of the city.

Syria army also took the strategic southern town of Sbeineh near Damascus on Thursday, threatening the militants-control of the wider area and cutting off a supply route for insurgents around the capital.

NJF/NJF