Battle for Aleppo escalates, U.N. sees 'bleak moment'

Syrian rebels fought fiercely with pro-government forces trying to advance into opposition-held areas of eastern Aleppo and warplanes kept up their bombardment of the area in a renewed bid by Damascus to retake the entire city, Reuters reported.

The U.N. humanitarian adviser said the besieged population of eastern Aleppo faced a "very bleak moment" with no food or medical supplies, winter approaching, and an increasingly fierce attack by Syrian and allied forces.

Violence also escalated in and around Damascus, where government forces bombarded the city's rebel-held eastern outskirts and rebels fired rockets into the government-controlled city center, witnesses said.