The Russian Ambassador to the UK has suggested Britain putting itself on “the wrong side of history” with warnings over atrocities in the Syrian city of Aleppo.

Alexander Yakovenko, whose government is supporting President Bashar al-Assad, claimed British officials were using information “fabricated by terrorists”.

“Murders and atrocities committed by terrorists are presented as those by the Syrian army, which fights for the liberation of its people from terror,” he said, according to the state-owned Sputnik news website.

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“We are surprised that the liberation of Aleppo by the Syrian army, the liberation of hundreds of thousands of Syrians, women and children from terrorists, the delivery of humanitarian aid to them by Russia is presented by British authorities as a tragedy of Syrian people.

"We cannot agree with this approach and would like to see the UK on the right side of history."

Syrian and Russian officials describe all anti-government groups as “terrorists”, despite appeals to operate under an international definition.

The UN has recorded atrocities by rebel groups, reporting some were preventing civilians fleeing their territories in Aleppo. Opposition fighters have also killed civilians living in regime-controlled districts with rocket attacks.

Mr Yakovenko claimed Russia and Syria were being subjected to “indiscriminate criticism” over their assault on rebel-held areas of Aleppo because of Britain’s calls for political transition.

His comments came amid widespread condemnation of the bombardment of civilian areas and reported massacres by Syrian government troops and their allies during the offensive on Aleppo.

Aleppo before the Syrian Civil War Show all 12 1 /12 Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War A man crosses a street in Aleppo, December 12, 2009 Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War A vendor sits inside an antique shop in al-Jdeideh neighbourhood, in the Old City of Aleppo, December 12, 2009 Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War A view shows part of Aleppo's historic citadel, overlooking Aleppo city, Syria Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War A view shows part of Aleppo's historic citadel, Syria Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War Visitors walk inside Aleppo's Umayyad mosque, Syria Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War People walk inside the Khan al-Shounah market, in the Old City of Aleppo, Syria Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War A man walks past shops in al-Jdeideh neighbourhood, in the Old City of Aleppo, Syria Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War People walk along an alley in al-Jdeideh neighbourhood, in the Old City of Aleppo, Syria Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War Visitors tour Aleppo's historic citadel, Syria December 11, 2009 Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War A general view shows the Old City of Aleppo as seen from Aleppo's historic citadel, Syria December 11, 2009 Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War People walk near Aleppo's Bab al-Faraj Clock Tower, Syria October 6, 2010 Reuters Aleppo before the Syrian Civil War Aleppo before the Syrian Civil War A man stands inside Aleppo's historic citadel, overlooking Aleppo city, Syria December 11, 2009 Reuters

Thousands of civilians and rebel fighters were being evacuated from the last remaining opposition districts as part of a ceasefire deal that offers a symbolic victory for Assad.

The area has been besieged and bombarded for months by Syrian and Russian forces, with the United Nations saying attacks on densely populated civilian areas “most likely constitute war crimes”.

Zeid Raad al-Hussein, the UN High Commissioner for Human Rights, said: “The Government of Syria is also obliged under international law to provide medical assistance to all sick and wounded people – civilians and fighters alike.”

Rescue service volunteers said ambulances attempting to evacuate wounded people from rebel districts were shot at on Thursday morning, while the convoy of 1,000 people was repeatedly delayed.

Speaking at an emergency meeting of the UN Security Council, Britain’s permanent representative said Assad’s forces were “redefining horror” with the support of Russia and Iran.

“Even wars have rules,” Matthew Rycroft said. “We urge the Assad regime and Russia and Iran to respect these rules and indeed to respect the will of the vast majority of Security Council members and the vast majority of members of the General Assembly.

Forces loyal to Syria's President Bashar al-Assad stand atop a damaged tank near Umayyad mosque, in the government-controlled area of Aleppo, during a media tour, Syria (Reuters)

To those who backed Assad and blocked action in this Council, we ask how can you side with such cruelty? How can you abide such an abuse of the UN Charter; words that we all claim to uphold?

Russia has repeatedly used its power of veto to stop UN Security Council resolutions against the bombing of Aleppo and prevent the Assad government’s referral to the International Criminal Court.

Fighters and their families are to be taken towards Idlib, a city in north-western Syria which is under rebel control, the Russian defence ministry said.

While Aleppo contained a plethora of rebel groups from moderate opposition fighters to Islamists and jihadis, Idlib province is largely controlled by Jabhat Fateh al-Sham, the former al-Qaeda affiliate previously known as Jabhat al-Nusra.

The stronghold is expected to be Assad’s next target and the respite for evacuated Aleppo residents may be short-lived.