U.S. Secretary of State John Kerry says it appears that air strikes and artillery shelling have stopped in the Syrian city of Aleppo and that a cease-fire brokered by Turkey and Russia may be taking hold there.
But Kerry accused Syrian President Bashar al-Assad of committing "nothing short of a massacre" in Aleppo -- saying that the international community now needs to exert pressure in order to move the process forward to implement the cease-fire in other parts of Syria.
Kerry's remarks on December 15 came after a day of evacuations from a rebel-held neighborhood of Aleppo under the truce deal.
Turkish President Recep Tayyip Erdogan said at least 1,150 civilians and wounded people had been evacuated from eastern Aleppo by nightfall.
Reports said a fourth convoy of evacuations was underway late on December 15.
Syrian state television and activists confirmed that convoys of buses were carrying evacuees from eastern Aleppo to opposition-controlled territory west of the city.
The World Health Organization's representative in Syria, Elizabeth Hoff, confirmed that her United Nations organization was involved in organizing the convoys.
Syrian state media reported earlier that the evacuation plan called for 4,000 rebels and their families to be evacuated from the remaining rebel-held part of Aleppo as part of the cease-fire deal.
Syria's ally Russia said Syrian authorities guaranteed the safety of rebels and their families who will be evacuated.
Rebel fighters and civilians had been due to leave eastern Aleppo on December 14, but an earlier truce brokered by Russia and Turkey collapsed.
Despite the successful launch of the evacuation operation, British Foreign Secretary Boris Johnson said late on December 15 that he had summoned the ambassadors of Russia and Iran to express his "profound disquiet" over recent events in Aleppo that have led to allegations from the United Nations of possible war crimes by Syria, Russia, and Iran.
French President Francois Hollande also criticized Russia for its role in the siege of eastern Aleppo, saying that Moscow had broken a promise to aid trapped civilians.
"Russia makes commitments that it is not keeping," Hollande said as he arrived in Brussels for a summit of European Union leaders. "There's a moment where you have to answer with action."
Francois Fillon, the conservative candidate seeking to succeed Hollande after a French presidential election next spring, said in Brussels that Western diplomacy has failed in Syria and suggested the way to end the bloodshed would be talks including those responsible for war crimes.
"I told European leaders that what we are forced to concede today is that Western diplomacy and in particular European diplomacy has failed," Fillon, a former prime minister, told reporters after meeting German Chancellor Angela Merkel and leaders of European center-right parties in Brussels, where an EU summit was also held.
He dismissed the option of a U.S. military intervention and said, "The other option is a strong European diplomatic initiative to bring around the table all those who can stop this conflict including those who have committed war crimes today."
The UN human rights chief said on December 14 that Assad's government and its allies in the war, Russia and Iran, probably committed war crimes by bombing civilians who were hoping to be evacuated from eastern Aleppo when a previous truce deal collapsed.
Zeid bin Ra’ad Zeid al-Hussein said that "the resumption of extremely heavy bombardment by the Syrian government forces and their allies on an area packed with civilians is almost certainly a violation of international law and most likely constitutes war crimes."
He also said the Syrian government "has a clear responsibility to ensure its people are safe, and is palpably failing to take this opportunity to do so."
Last week, Russia and China vetoed a United Nations Security Council resolution pushed by Western powers and calling for a seven-day truce in Aleppo, Syria's most populous city before the war.
Rebels had controlled the eastern part of Aleppo since 2012, but government forces have recaptured most of it in recent weeks.
Russia has given Assad crucial military and diplomatic backing throughout the conflict, which began with a forceful government crackdown on pro-democracy protesters in 2011 and erupted into a civil war that has killed more than 250,000 people.
Moscow helped turn the tide of the war in the government's favor with a major campaign of air strikes that began in September 2015 and which Western governments say has mainly targeted rebels rather than Islamic State militants.