For the first time since a lethal attack on a UN aid convoy this week, aid trucks were again rolling inside Syria to bring food and medical supplies to tens of thousands of people in rural Damascus on Thursday.
The attack on Monday killed 21 people and destroyed 18 trucks and their cargo, forcing the UN to temporarily halt convoys inside the country, while worsening tensions between Russia and the US, as Washington blamed Moscow for the bombing.
More aid deliveries could go ahead in the coming days if the mission succeeds. Millions of people in Syria rely on humanitarian aid, though many areas of the country are under siege, largely by President Bashar al-Assad's forces, and go without help.
And yet while relief was heading to 35,000 people in besieged opposition-controlled Moadamieh, in rural Damascus, the rebel-held eastern city of Aleppo, in the north of the country, was being bombarded by airstrikes that left at least 11 people dead, a monitoring group said.
Eastern Aleppo has been cut off from humanitarian assistance since July, and 40 trucks remain stuck at the Turkish border, unable to enter the enclave.
"Please, President Assad, do your bit to enable us to get to eastern Aleppo and the other besieged areas," Jan Egeland, a senior UN advisor on humanitarian efforts in Syria, pleaded from Geneva.
Egeland added that the rebels had yet to give their approval for aid to be delivered to eastern Aleppo.
Activists say Syrian or Russian warplanes dropped incendiary bombs on eastern Aleppo along with more than 200 missiles that landed in the area overnight.
"The whole city was on fire during the night," said Ibrahim al Hajj, a spokesman for the White Helmets rescue group, which operates in rebel-held areas of Syria.
A ceasefire brokered by the US and Russia collapsed on Monday, after largely holding for a week, when Syrian planes began attacks on rebel-held areas.
US Secretary of State John Kerry is still keen to reinstate the ceasefire, despite pessimism voiced by top Russian officials, but has demanded Moscow and Damascus abide by the terms.
"I believe that to restore credibility to the process, we must move forward to try to immediately ground all aircraft flying in those key areas in order to de-escalate the situation and give a chance for humanitarian assistance to flow unimpeded," Kerry said Wednesday.
"And if that happens, there is a chance of giving credibility back to this process."
Iranian President Hassan Rouhani on Thursday rejected the idea of grounding flights, saying there was "no logic" to stopping the air force, which was the Syrian government's only military advantage had against terrorist groups.
"If you ground flights, you are aiding the terrorists - whether you like it or nor," Rouhani told reporters.
The UN says it plans to try to restart more wider-reaching peace talks in the coming weeks, though previous efforts have barely got off the ground.
UN Secretary-General Ban Ki-moon this week was sharply critical of al-Assad's government, which regularly denies any wrongdoing.
"Many groups have killed innocent civilians — none more so than the government of Syria, which continues to barrel bomb neighborhoods and systematically torture thousands of detainees," said Ban.
Meanwhile, some 350 rebel fighters and their families began to evacuate al-Waer, a hard-hit area of Homs city in the centre of the country, under a deal reached between rebel groups and the Syrian government.
The deal stipulates the district, where tens of thousands of people still live, will get aid. Rebel factions in other parts of the country have been critical of the fighters in al-Waer agreeing to a deal, despite the desperate situation.
Veiled women and bearded men, along with children, were seen carrying their bags and leaving in green buses escorted by the Syrian Red Crescent.
The Syrian government claims only hardline Islamic armed groups are in al-Waer.
Also, 11 people, including a local opposition official, were killed in a suicide attack in the southern province of Daraa, the Syrian Observatory for Human Rights reported. Turkish media reported a second suicide bombing in Azaz, a rebel-held area near the border, blaming Islamic State.