Syrian activists reported Wednesday that rebel shelling and government airstrikes near Damascus killed at least 36 people.
The new violence erupted in the hours before Iranian Foreign Minister Mohammad Javad Zarif arrived in the Syrian capital. He headed straight into talks with President Bashar al-Assad about Tehran's new plan to end Syria's years-long civil war that it wants to offer to the United Nations.
The British-based Syrian Observatory for Human Rights, which monitors violence in the country, said rebel shelling began during the morning. The attacks killed five people and wounded another 60.
The watchdog group said government fighter jets responded with attacks on rebel-held areas in the Damascus suburbs, killing 31 and injuring more than 120 others.
Syria's state-run SANA news agency blamed "terrorists" for the mortar and rocket fire on Damascus.
The government has routinely referred to rebels as "terrorists" throughout the conflict that began in March 2011 as peaceful protests before exploding into a civil war that has left more than 240,000 people dead. Another 11.6 million people have been forced from their homes, according to the United Nations.
Zarif talked about the Iranian peace plan during a stop earlier in Lebanon, where he met with the leader of the militant group Hezbollah.
Syrian troops have been joined by Hezbollah fighters, including in Idlib province where the pro-government forces began a 48-hour cease-fire with rebels Wednesday in the town of Zabadani and two villages, Foua and Kfarya.
The Observatory said the two sides are negotiating the withdrawal of rebels from Zabadani, near the Lebanon border, as well as the end of a siege against the villages.