The United Nations called on world powers on Thursday to help arrange the medical evacuation of 500 people, including 167 children, from eastern Ghouta, saying the besieged Damascus suburb has now become a "humanitarian emergency".
Nine people died in recent weeks waiting for permission from the Syrian government for the sick and wounded to be evacuated from the rebel-held area to hospitals less than an hour drive from the capital, said Jan Egeland, the UN humanitarian adviser on Syria.
Russia and Iran, as well as the United States and France, pledged to help during the weekly humanitarian meeting, he said.
"It would be incredible if they cannot deliver a simple evacuation of mainly women and children, a 40-minute drive to Damascus city," Egeland told a news conference in Geneva.
"We are convinced that we can do the evacuation if we get a green light from the government. We can then negotiate calm with both sides."
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Dozens of mortar bombs landed on Ghouta, the last major rebel stronghold near Damascus, on Wednesday, a war monitor and a witness said, despite a 48-hour truce proposed by Russia to coincide with the start of peace talks in Geneva.
"Eastern Ghouta, next door to Damascus, is the eye of the hurricane, it is the epicentre of this conflict. At the moment there are 400,000 people there," Egeland said.
In the past two months, UN convoys have delivered supplies to only 68,000 of the 400,000 trapped civilians, he said.
Our not being able to reach eastern Ghouta for many months in most of areas has now led to an undoubtedly catastrophic situation,
Acute malnutrition rates among children there is nearly 12 percent, above the 10 percent emergency threshold, and a five- or six-fold increase since January, he added.
"In general I would say that no, there is no calm in this de-escalation zone, there is only escalation in this de-escalation zone," Egeland said. "That has ended in eastern Ghouta except for (a pause of) two days only, there has been massive loss of civilian life, hundreds and hundreds have been wounded." "We need sustained calm to be able to feed 400,000 people who now beyond doubt are in a humanitarian emergency"," he said.
Civilians in Damascus have also been killed or wounded by mortars coming from easternGhouta, he added.
In Hassakeh, in northeastern Syria, UN aid workers found a desperate situation, Egeland said. "They told about children walking around barefoot, recently displaced children, barefoot in the snow and the cold."
He hoped that the UN Security Council would agree on a resolution allowing cross-border aid to continue to enter Syria, supplying 2.7 million people in rebel-held areas.
"It is my clear understanding from all members of the Security Council that none wants a break of the pipeline."