In Geneva, UN humanitarian adviser Jan Egeland called on parties to allow aid convoys to reach besieged and hard-to-reach areas of Syria to demonstrate “goodwill” before envoys gather for talks on 23 February.
Egeland lamented that not a single UN-arranged land convoy has reached any of more than a dozen besieged towns or villages this year, citing a lack of approvals from authorities.
The UN envoy for Syria, Staffan de Mistura, was meanwhile meeting with top Russian officials in Moscow in the run-up to the anticipated start of Syrian peace talks in Geneva.
It says government forces have responded with a relentless barrage of artillery and airstrikes, destroying at least one field hospital in the contested provincial capital, also called Daraa.
Issam al-Rais, a commander in the rebel Free Syrian Army’s Southern Front, said mainstream rebel factions were also taking part in the fighting, in response to persistent government violations of the 30 December ceasefire.
“If the regime disciplines itself, then we are committed to the ceasefire,” al-Rais told the AP.
The two sides are about 5 kilometers (3 miles) apart.
The Observatory said 24 civilians have been killed under Turkish and Syrian opposition fire in al-Bab in the past 24 hours. The figure could not be independently confirmed.