UN chief Ban Ki-moon on Thursday condemned attacks against civilians in Syria, in particular the aerial attacks with explosive-packed barrel bombs.
More than 250 people -- including 76 children -- have been killed in six days of such regime attacks on the city of Aleppo, according to the Syrian Observatory for Human Rights, an NGO.
"The Secretary-General is following with deep concern the continued armed escalation in Syria, most deplorably the ongoing aerial attacks and the use of 'barrel bombs' to brutal, devastating effect in populated areas," said Ban's spokesman, Martin Nesirky.
"He condemns once again the indiscriminate use of any weapon against civilians, in contravention of obligations under international humanitarian and human rights law," Nesirky said. "All civilians must be protected in any situation."
The bombings, which began Saturday, have sparked a mass exodus from worst-hit parts of the city.
Ban urged all sides to "immediately" work on reducing violence and finding a peaceful resolution to the bloody, three-year conflict.
"The Secretary-General reiterates that further violence serves the agendas of those who see military means as the only way forward, at the expense of the Syrian people," Nesirky said.