UNITED NATIONS -- This week, in pointed testimony, President Trump’s new U.N. Ambassador Nikki Haley sparred with the Russian Ambassador during a vote on a resolution intended to hold individuals accountable for chemical weapons attacks in Syria.

“Russia and China made an outrageous and indefensible choice today,” Haley said after both nations used their veto power to block the resolution. “They turned away from defenseless men, women, and children who died gasping for breath when Assad’s forces dropped their poisonous gas.”

Russian Deputy Ambassador Vladimir Safronkov defended his country’s veto, saying the, “odious and flawed anti-Syrian draft is absolutely unacceptable.”

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A day later, however, as the Syrian conflict enters its 7th year and fragile peace talks continue, the United Nations was presented with yet more evidence of war crimes committed by Syrian President Bashar Assad against his own people -- and against international aid providers.

The U.N.’s own Geneva-based Commission of Inquiry on Syria presented a report on the use of chemical weapons, cluster munitions, and indiscriminate bombing of civilians in the final months of the battle for rebel-held eastern Aleppo, from July to December 2016, that details just how brutal the conflict has been.

Paulo Pinheiro, the Commission Chair, reported relentless bombing by Syrian and Russian forces in Aleppo.

“The scale of what happened in Aleppo is unprecedented in the Syrian conflict,” he said. “The deliberate targeting of civilians has resulted in the immense loss of human life, including hundreds of children.”

“For months,” Pinheiro said, “the Syrian and Russian air forces relentlessly bombarded eastern Aleppo city as part of a strategy to force surrender. Hospitals, orphanages, markets, schools and homes were all but obliterated.”

In at least two incidents, the report states, chlorine bombs were dropped by Syrian aircraft in an effort to evacuate residential areas, causing civilian casualties.

The report from the Commission, which falls under the auspices of the U.N.’s Office of the High Commissioner for Human Rights, also concluded that Syrian government aircraft deliberately bombed a humanitarian aid convoy of the U.N. and Syrian Red Crescent at Orum al-Kubra, in western Aleppo, in September.

The evidence, Pinheiro said, was irrefutable: “We have established very clearly in the report that the Syrian air force is responsible for these attacks.” He said there was no evidence linking Russia specifically to the attacks on the aid convoy.

The aerial campaign in Aleppo detailed in the report amounts to war crimes committed, according to its authors.

The report also pointed to war crimes by opposition groups, which shelled government-controlled western Aleppo, killing and injuring dozens and using civilians as human shields. Both sides, the report said, carried out indiscriminate attacks in densely populated civilian areas.

Earlier in the week, when the Resolution on Syria was blocked, U.S. Ambassador Haley told the Council that, “investigators spent a year collecting mountains of evidence, speaking to witnesses, and verifying testimony. The conclusion was and remains irrefutably clear: The Assad regime used chemical weapons three times from 2014 to 2015, and ISIS used chemical weapons once.”

“We will roll up our sleeves and work relentlessly to bridge this inconceivable gap in the Security Council,” France’s Ambassador Francois Delattre told reporters. “We owe it to the victims of these barbaric acts.”

“What we have seen here in Syria, I never saw that in Rwanda, or in former Yugoslavia, in the Balkans,” added commission member Carla del Ponte.

After the commission’s report was released on Wednesday, Britain’s Ambassador Matthew Rycroft said it, “shows the depravity of the Assad regime.”

The report comes as peace talks continue between the Syrian government and the opposition; negotiators in Geneva this week hope to forge an agreement on an agenda brokered by U.N. Syria envoy Staffan de Mistura, to include discussion of elections, the constitution, governance -- and fighting terrorism -- in Syria.

The report also comes as Russian aircraft mistakenly bombed Syrian fighters who were being trained by the United States, according to reports, as both the U.S. and Russia turn their attention to fighting ISIS.