Two rebel groups say they have have formed a joint command in Aleppo, a move that could improve the chances of the rebels increasing their control over the Syrian province.
Allies of the Syrian opposition have repeatedly called for the rebels to unite as a precondition for military support from the West.
But anti-regime fighters remain largely divided across the country.
Al Jazeera's Hashem Ahelbarra reports.
Source: Al Jazeera