At least 32 civilians have been killed in Aleppo in the past 24 hours as Syrian government warplanes and artillery hit rebel-held districts of the city for a second day.
The renewed bombardment has damaged two hospitals, a blood bank, and residential buildings in the city's eastern neighborhoods.
The attack, the first Russian strike from the Mediterranean-based carrier Admiral Kuznetsov, was described Tuesday by the Kremlin as targeting extremists in Idlib and Homs provinces, but it also sparked criticism from Washington and the United Nations.
The Britain-based monitor, the Syrian Observatory for Human Rights, said six children were among the 32 people killed.
A medical organization, the Independent Doctors Association, reported barrel bomb attacks damaged the children's hospital and the only blood bank in eastern Aleppo.
Medical facilities have regularly been hit, and sometimes completely destroyed, in the government's fight against rebels, though Damascus and Moscow deny they have targeted hospitals.
The Russian Defense Ministry said a navy frigate also launched long-range cruise missiles at targets in northern Idlib, an area about 60 kilometers southeast of Aleppo.
But the ministry insisted the Russian strikes were limited to Islamic State and other extremist targets, and ministry spokesman Igor Konashenkov rejected media reports alleging that Russian warplanes were involved in strikes on a hospital in Aleppo.
"Aircraft of the Russian Aerospace forces have delivered no airstrikes in Aleppo for the past 28 days," he said.
Syrian President Bashar Assad said in an interview broadcast Tuesday with Portugal's state-run RTP television channel that government troops are fighting to free civilians from “terrorists,” even though most of the rebels in Aleppo, around 8,000 according to the U.N., are Syrians who have been fighting to overthrow Assad.
In Washington, the State Department blasted Moscow for the new attacks.
"We strongly condemn the resumption of airstrikes in Syria by the Russians," spokeswoman Elizabeth Trudeau said. She also accused Russia of blocking shipments of food and other aid to Aleppo during the bombing lull, a move she said led residents to "starve while [Moscow sought] praise from the international community for halting indiscriminate strikes."
White Helmets, a local civil defense rescue group, said Wednesday 11 civilians were killed in the Sukkari neighborhood.
"We worked through the night to lift the debris and remove the martyrs and surviving civilians, and now we're trying to remove the rubble blocking the roads," Yahya Arja, a White Helmets volunteer, said.
The renewed violence in Aleppo comes after U.S. President-elect Donald Trump spoke by telephone with Russian President Vladimir Putin, the Syrian government's strongest ally in the five-and-a-half-year civil war.
Putin said Monday that he and Trump agreed to "combine efforts to tackle international terrorism." But it remains unclear whether the two governments can agree on a formula for easing the conflict, which the United Nations says has claimed more than 400,000 lives since 2011.
Moscow and Damascus categorize all rebels seeking to oust the Assad government as terrorists, a definition both governments use to justify the deadly and apparently indiscriminate bombings in eastern Aleppo.
Washington has supported the rebels fighting against Assad’s government.
But this support could change under the Trump’s administration, as Assad told Portugal's RTP that he welcomes Trump's campaign comments that Washington's involvement in Syria should be focused exclusively on fighting jihadists.
Western governments and the United Nations have framed the Aleppo onslaught as a vast humanitarian crisis, with diplomats and human rights organizations arguing that both Damascus and Moscow could face future war crimes inquiries for their roles in the destruction of eastern Aleppo.