Syrian airstrikes on rebel-held areas of Aleppo have killed ten more civilians, lifting the city's nine-day death toll to nearly 250. US Secretary of State John Kerry is heading back to Geneva in a fresh ceasefire bid.
Russia has rejected calls to rein its ally Syrian President Bashar al Assad and his forces, as more residents fled Syria's divided and battered northern city.
The fight for Aleppo was part of Assad's campaign against "the terrorist threat," said Russian Deputy Foreign Minister Gennady Gatilov, in reply to a Washington appeal to keep Assad in check.
The past week's resurgence of air strikes and shelling in Aleppo has severely tested an internationally mediated truce reached on February 27 and further peace talks between the regime and non-jihadist rebels.
Elsewhere in Syria, truce efforts seemed to be working. The Red Cross says aid deliveries to two northern and two southern towns of Syria have proceeded.
Claim and counter-claim
The Britain-based Syrian Observatory for Human Rights said its monitors had observed 28 air strikes on rebel-held eastern neighborhoods on Saturday in Aleppo, where an estimated 250,000 people remain.
But, Russia's defense ministry said it had recorded only "three ceasefire violations," blaming them all on rebels. Syria's state news agency SANA blamed the al Qaeda affiliated al Nusra Front and its allies.
Only one escape route
Families tried to flee by using eastern Aleppo's only route along the dangerous Castello Road, as the International Committee of the Red Cross (ICRC) deplored attacks on four Aleppo medical facilities on Friday.
ICRC Syria spokesperson Marianne Gasser said attacks on hospitals and clinics were "strictly prohibited under international humanitarian law."
"For the sake of people in Aleppo, we call for all to stop this indiscriminate violence."
'Top priority,' says US
Amid reports that Kerry would travel back to Geneva on Sunday, the US State Department said the top US diplomat was giving "top priority" to ending the violence in Aleppo.
Kerry had had phone calls with the United Nation's Syria envoy Staffan de Mistura and Riyah Hijab, a negotiator for Syrian opposition groups, said State Department spokesman John Kirby.
The head of the main Syrian opposition coalition, Anas al-Abdeh, said the chances of a solution were fading unless the international community acted fast - before the formal start of UN-backed peace talks on May 10.
Speaking after a coalition meeting in Istanbul, Abdeh claimed that Assad's regime "is not really interested in a political solution."
Abdeh said it was up to Washington, which in recent months had engaged in intense diplomacy with Moscow - to salvage the Geneva peace process.
"I hope the Americans are doing that, otherwise all the good efforts of the past four months would go in vain," he said.
Aid convoys bring relief
In Damascus, another ICRC spokesman said humanitarian convoys run jointly with the UN and Syrian Red Crescent had begun delivering food and medicines to two outlying rebel-held towns besieged by government forces - Madaya and Zabadani.
At the same time, other convoys had entered the two government-held towns besieged by insurgents near Aleppo - Fuaa and Kafraya.
Madaya, in mountains northwest of Damascus, is the town where dozens of residents died of starvation late last year.
ipj/jr (AFP, AP, Reuters)