Stalemate in battle for Syria's second city Aleppo?

An assault launched by rebels to drive government forces out of Syria's second city, Aleppo, appears to have reached an impasse.

Despite its superior air power, artillery and tanks, the army has failed to drive the rebels out of the city. Parts of Aleppo have been devastated by the fighting.

The city's medieval souk - a Unesco world heritage site - has become the latest casualty of the conflict.

Jim Muir reports from Beirut.