The Doctors Without Borders (MSF) charity accused Syria's government and its ally Moscow of provoking a "bloodbath" in the city, saying the eastern rebel-held portion had become "a giant kill box".
Syria's army was advancing on two Aleppo fronts, as talks between key players Washington and Moscow -- which back opposing sides in the war -- appeared close to collapse.
Damascus's bid to recapture all of the divided northern city prompted the UN to warn of "a humanitarian catastrophe".
The UN panel will report to Ban, who will "decide what further steps to take", a UN statement said.
Also Read
Just over a week after Syria's army announced an operation to recapture all Aleppo, it was advancing both in northern and central Aleppo Friday, according to the Syrian Observatory for Human Rights monitor and state media.
In the north, it recaptured the Handarat former Palestinian refugee camp, as well as the old Kindi hospital, said Observatory director Rami Abdel Rahman.
The Observatory said at least 15 people, including two children, were killed in strikes on Heluk and other eastern districts today.
In central Aleppo, meanwhile, fierce clashes shook the Suleiman al-Halabi neighbourhood, which is divided by the frontline separating the rebel-held east and regime-held west.
The army is seeking to capture the opposition-held sector of the district and advance to the main water supply station for the government-controlled part of Aleppo which is in the neighbourhood.
State television said 15 civilians had been killed and 40 wounded by rocket fire into the government-held part of Suleiman al-Halabi and neighbouring Midan district.
The assault has levelled apartment blocks and put hospitals out of service, creating a humanitarian catastrophe in opposition areas besieged for most of the past two months.
It has been some of the worst violence since the March 2011 beginning of Syria's conflict, which has killed more than 300,000 people and displaced over half the population.
Disclaimer: No Business Standard Journalist was involved in creation of this content