Syrian regime forces were on the defensive around Aleppo on Sunday after a rebel alliance said it inflicted a major setback by breaking a three-week government siege of the battered city.
Rami Abdel Rahman, head of the Syrian Observatory for Human Rights, said the development was one of the most significant setbacks for government forces since the conflict erupted in March 2011.
"Despite more than 600 Russian strikes, the regime forces were not able to hold onto their positions," he said.
Steadfast regime ally Moscow has provided air support for forces loyal to President Bashar al-Assad since September 2015.
(AFP)