The government assault on the northern city has spurred a mass exodus of tens of thousands of residents from the opposition-held east and prompted fresh calls by Russia for aid corridors.
President Bashar al-Assad's forces captured the city's northeast this week and were focused on seizing Sheikh Saeed, a large district on the city's southeast edges.
But anti-government fighters put up a strong defence there overnight, rolling back recent government gains, according to the Syrian Observatory for Human Rights.
"But rebels put up ferocious resistance, because they knew they would be trapped if Sheikh Saeed fell," Abdel Rahman added.
Also Read
The head of the Britain-based monitor said opposition forces were now once again in control of at least 70 per cent of the neighbourhood.
Sheikh Saeed borders the last remaining sections of Aleppo still in rebel hands -- a collection of densely populated residential neighbourhoods where thousands have sought refuge from advancing regime forces.
More than 300 civilians, including dozens of children, have been killed in east Aleppo since the government began its offensive on November 15, according to the Observatory.
Retaliatory rocket fire by the rebels on government-held western areas of the city has killed 55 civilians, the monitor says.
According to Syrian state news agency SANA, one civilian was killed and three were wounded Friday in rebel rocket attacks.
Disclaimer: No Business Standard Journalist was involved in creation of this content