Syrian state media says government forces backed by members of Lebanon's Shiite Hezbollah group are advancing from different directions in the mountain resort of Zabadani near the border with Lebanon.

The ultraconservative Ahrar a-Sham insurgent group said Wednesday that it has stopped communicating with Iranian mediators after they insisted that fighters and residents leave the resort.

Ahrar al-Sham said the government aims to clear out the area's Sunni Muslim population.

Syrian troops and Hezbollah have been besieging Zabadani since early July, and have faced strong resistance from gunmen inside the resort.

Syria's state news agency SANA said the fighting has left dozens of militants dead.

The capture of Zabadani would tighten Hezbollah's grip on Syrian territories bordering Lebanon.