Opposition activists claim a military bombardment of a town in central Syria killed 35 people on Monday.
Those deaths come 24 hours after as many as 40 died as Syrian forces pounded a number of towns.
From Idlib in the north to Deraa in the south reports suggest the shelling has been stepped up with 17 children and eight women among the dead close to Hama.
A hospital where bodies had been taken was targeted by government helicopters say activists.
Politicians have reacted to the growing violence with the Turkish Deputy Foreign Minister, Naci Koru saying, “April 10 has become void” in reference to the peace plan.
Russia, which remains President Bashar Assad’s most important ally, stopped short of pressing him to rein in his army. “Everything must follow from respect for Syria’s sovereignty and violence must be stopped,” said the Deputy Foreign Minister Gennady Gatilov.