Syrian warplanes had bombed the opposition-held Idlib province, killing at least 22 people according to the Syrian Observatory for Human Rights in London.
Idlib, a province crucial to holding the nearby city and Syrian capital Aleppo, had fallen back to pro-government forces after Syrian opposition rebels had relinquished control.
About 26 air strikes had been counted across the province.
Idlib is one of the last strongholds of the Syrian Opposition group. Idlib has become a refuge for many who had tried to escape the violence in Aleppo.
In support of Syrian government forces, Moscow had sent its own air strikes against Syrian rebels for about a year.
Outside Idlib, Syrian rebels and regime forces fought in a major power plant in the Hama province. According to the Observatory, governmetn airstrikes and shelling on opposition areas in Aleppo city and surrounding countryside had killed about 40 civilians on Saturday.
State media and the Observatory said opposition shelling on government-held districts of Aleppo city killed nine civilians, including two children. State media said another 22 people were wounded. Fighting for the city has intensified this summer, after regime troops seized control of the last supply route into opposition-held areas in mid-July. After a nearly three-week siege, opposition forces took Ramussa on August 6, linking up with opposition-held neighborhoods