The Syrian army captured a major district of Aleppo on Monday from rebel fighters, now confined to a small pocket of their former bastion in the city's east.

Government forces held more than 90 percent of the onetime opposition stronghold, a monitor said, and appeared on the verge of retaking the whole city.

The fall of Aleppo would deal rebels their worst blow since the beginning of Syria's conflict in 2011, and leave the government in control of the country's five major cities.