UN criticises Russia over Aleppo "war crimes"

Russia's involvement in Syrian army offensives in the city of Aleppo has come under increased scrutiny from the United Nations, which has described the actions as "war crimes".

An urgent meeting was held yesterday at the request of Britain, the US and France, as Syria's biggest city struggles to cope with its worst siege of the lengthy conflict.

French foreign minister Jean-Marc Ayrault was one of those who called on Russia and Iran to use their influence to call a halt to violence.

"I am calling on Russia and Iran to pull themselves together and show responsibility, by putting a stop to this strategy," Ayrault said. "If not, Russia and Iran will be accomplices in war crimes committed in Aleppo."

Britain's UN ambassador Matthew Rycroft added that Russia had a responsibility to act.

"Aleppo is burning," he said "And to cap it all, water supplies, so vital to millions, are now being targeted, depriving water to those most in need. In short, it is difficult to deny that Russia is partnering with the Syrian regime to carry out war crimes."

Over 200 civilians are thought to have died in the five-day pummeling of rebel-held areas of Aleppo, with a quarter of a million people trapped in the region.

A ceasefire in the conflict that provided hope that the US and Russia could come to an agreement was broken last week.

On Sunday, British foreign minister Boris Johnson also accused Russian president Vladimir Putin of being directly involved in the war.

"Putin's regime is not just handing Assad the revolver; he is in some instances firing the revolver. The Russians themselves are actually engaged."