Rebel fighters say they need support to battle Syrian government forces in Aleppo in the country's north.
The Free Syrian Army says it is trying to defend the area from a military force armed with helicopters, tanks and a lot of artillery - far superior to the weapons and supplies the FSA has.
But other opposition groups nearby seem to have acquired the kind of weapons being sought. The rebels say they are using Russian-made Grad rockets to target Syrian army bases.
Al Jazeera's Caroline Malone explains.