Several members of the United Nations Security Council condemned the Syrian regime and its Russian ally over a chemical weapons attack in the city of Douma in 2018.
But in the latest example of the great power divide crippling the UN's highest decision-making body, France, Britain and the United States, known as the P3 clashed with representatives from Russia and Syria, who called the allegations a "hoax".
The Security Council showdown followed the release of a report by the OPCW (Organisation for the Prohibition of Chemical Weapons) last week, which concluded there were "reasonable grounds to believe that the Syrian Arab Air Forces were the perpetrators of the chemical weapons attack".
The OPCW investigation found that "on the evening of 7 April 2018, at least one helicopter of the Syrian "Tiger Forces" Elite Unit dropped two yellow cylinders containing toxic chlorine gas on two apartment buildings in a civilian-inhabited area in Douma, killing 43 named individuals and affecting dozens more".
Brandishing a copy of the document in the Security Council chamber, the UK ambassador Barbara Woodward called it: "Yet again … undeniable evidence that the Syrian state has used chemical weapons to murder its own citizens"
She also said that the Assad regime had been rebuilding its stockpile of chemical weapons since 2018.
"No amount of disinformation can conceal the guilt of the regime and its allies," said Nicolas de Rivière, the ambassador of France to the UN.
The US joined the chorus of condemnation, urging council members not to overlook the role of Russian forces.
"The report highlights that Russian forces were co-located at the base from which Assad's helicopters launched their deadly chemical attack and that they controlled the airspace over Douma along with the Syrian air force," said US Under Secretary for Arms Control, Bonnie Jenkins.
But the Russian and Syrian representatives dismissed the report out of hand. Russia’s permanent representative, Vassily Nebenzia, labelled it "lies and fabrications" and an attempt to settle "political scores on behalf of western states".
The representative of the Syrian Arab Republic, Bassam Sabbagh, called the allegations a "staged charade".
China, meanwhile, cast doubt on the methods and procedures of the OPCW investigation into the attack.
After the Security Council meeting, the ambassadors of the P3 along with non-permanent members Ecuador, Switzerland, Malta, Japan and Albania lined up outside the chamber to deliver a statement, calling for accountability for the perpetrators and justice for the victims.
But by then, the ambassadors from Russia and Syria had already made their way to the UN press briefing room to present their own - opposing - narrative.
The two envoys set about skewering the report and its authors, and played an excerpt from a documentary to the gathered media, claiming the 2018 incident in Douma was staged by "western enemies".
This has become a familiar pattern at the United Nations. Russia has previously said reports of atrocities in Ukraine were false flag events by western powers to justify military escalation.
As the great power divide at the UN Security Council intensifies, so does the battle for truth.