British ambassador Matthew Rycroft joined his US and French counterparts in walking out of an emergency session of the UN Security Council on Sunday in a show of anger at the latest offensive by the Syrian regime to take the beleaguered city of Aleppo.
Earlier the Russian Foreign Ministry hit back at Foreign Secretary Boris Johnson after he warned Moscow would be guilty of committing war crimes if its warplanes were deliberating striking civilian targets.
Mr Rycroft told the security council meeting in New York that it was “difficult to deny” that the Syrian regime of President Bashar Assad and his Russian allies were engaged in committing war crimes.
“After five years of conflict, you might think that the regime has had its fill of barbarity – that its sick bloodlust against its own people has finally run its course,” he said.
“But this weekend, the regime and Russia have instead plunged to new depths and unleashed a new hell on Aleppo.”
The UN special envoy on Syria, Staffan de Mistura, said the offensive to take the city had unleashed “unprecedented military violence” on its inhabitants, killing at least 213 civilians, many of them women and children.
He said there had been reports of the use of bunker-busting bombs and incendiary weapons which created “fireballs of such intensity that they light up the pitch darkness in Aleppo as if it were daylight”.
His intervention prompted fresh recriminations between Russia and the United States with US ambassador Samantha Power accusing Moscow of “barbarism”.
She urged security council members to “have the courage to say who is responsible for this and in a single voice tell Russia to stop”.