Syrian regime forces and allied fighters advanced quickly inside opposition-held Aleppo on Monday (November 21st), AFP reported.

The Syrian Observatory for Human Rights said regime forces backed by Iranian and Russian troops and fighters from Lebanon's Hizbullah had captured the eastern part of the Masakan Hanano neighbourhood.

"It is the most important advance inside the eastern neighbourhoods that the regime has made so far," said Observatory director Rami Abdel Rahman.

"If they take control of Masakan Hanano, the regime will have line of fire control over several opposition-held neighbourhoods and will be able to cut off the northern parts of opposition-held Aleppo from the rest of the opposition-held districts."

On Sunday, the regime rebuffed a UN truce plan for Aleppo that would see the east of the city temporarily administered by the opposition.

The Observatory says more than 100 people have been killed in east Aleppo since the regime's latest bombardment began last Tuesday, with at least five civilians killed in ongoing bombing on Monday.

Opposition fighters also have fired rockets onto regime-held west Aleppo, killing 10 people including eight children on Sunday.

The UN's Syria envoy Staffan de Mistura warned that time was "running out" for eastern Aleppo, adding that there was concern about "an acceleration of military activities" in Aleppo and beyond.