UN Secretary General Ban Ki-moon has raised alarm over “reports of atrocities against a large number of civilians, including women and children” in Aleppo, his spokesman said.
Syria’s army, loyal to President Bashar al-Assad, are reportedly close to capturing all of east Aleppo which has been a rebel stronghold in the country's civil war.
Residents in the besieged areas of the city have described the situation as “doomsday”, with many unable to flee the fighting.
“Families got together awaiting death together. This is what’s happening,” one activist wrote in a Whatsapp message to journalists on Monday.
“The Secretary-General is conveying his grave concern to the relevant parties. He has instructed his Special Envoy for Syria to follow up urgently with the parties concerned,” UN spokesman Stephane Dujarric said in a statement.
“While stressing that the United Nations is not able to independently verify these reports, the secretary-general is conveying his grave concern to the relevant parties.
“He has instructed his special envoy for Syria to follow up urgently with the parties concerned,” the statement added.
The United Nations humanitarian adviser on Syria, Jan Egeland, said in an earlier tweet on Monday that the Syrian and Russian governments must be held responsible for atrocities committed by militias loyal to President Bashar al-Assad in Aleppo.
“The Gov'ts of Syria & Russia are accountable for any and all atrocities that the victorious militias in Aleppo are now committing!” Mr Egeland tweeted, as President Assad's forces bombarded the last rebel-held pockets in eastern parts of the city.
Russia and Syria’s governments are yet to issue public statements on the issue.
The final stages of the battle are expected to conclude swiftly. The Syrian military claimed to have taken control of 98 per cent of rebel-held east Aleppo early on Monday morning after seizing the large industrial district of Sheikh Saeed.
“They [the rebels] don't have much time. They either have to surrender or die,” Lieutenant General Zaid al-Saleh, head of the government's Aleppo security committee, told reporters.
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