The UN envoy to Syria has urged the US and Russia to urgently intervene “at the highest level” to salvage talks.
Speaking after briefing the UN Security Council on the faltering peace process, Staffan de Mistura said that a truce agreed in February was “barely alive”.
At least 20 civilians were reportedly killed on Wednesday in government strikes on a hospital and nearby residential building in eastern Aleppo.
Civil defence volunteers, known as the White Helmets, told French news agency AFP that the dead included children and the only paediatrician left in rebel-held areas of the city.
Calling on the US and Russia to cooperate, de Mistura said that the legacies of both President Barack Obama and President Vladimir Putin were linked to the success of the peace process in Syria.
de Mistura said that the fragile “cessation of hostilities” established in February had been “saved from total collapse” but “could collapse any time”.
He said that over the past 48 hours an average of one Syrian had been killed every 25 minutes and one wounded every 13 minutes, reports the BBC.
