A humanitarian convoy, reportedly carrying the injured out of beleaguered eastern Aleppo, has come under fire by pro-Assad forces, activists have claimed.

Pictures shared on social media show individuals participating in the convoy bloodied and wounded in the shootings. Differing reports have claimed one person was killed and anywhere between two and four people were injured as they attempted to move a barrier blocking the convoy's progress.

The alleged attack will put into jeopardy a tentative ceasefire in Aleppo which faltered yesterday during negotiations over the evacuation of thousands of civilians and fighters still inside the last rebel-held enclave of the city.

Reports of the shooting came hours after the Syrian military and Hezbollah, which is fighting alongside the Assad regime, confirmed the evacuation of east Aleppo was imminent, according to AP.

A ceasefire brokered between Ankara and Moscow yesterday (14 December) unravelled as Iranian-backed militias insisted the deal for rebel fighters also needed to include safe passage for its combatants from the Shia majority towns of Foua and Kefraya

Syrians walk over rubble of damaged buildings, while carrying their belongings, as they flee clashes between government forces and rebels in Tariq al-Bab and al-Sakhour neighborhoods of eastern Aleppo Reuters

The United Nations said the devastating onslaught by pro-Assad forces on the east of the country in recent days could constitute war crimes.

Forces loyal to President Bashar al-Assad are reported to have killed at least 82 civilians in cold blood, including women and children, according to the UN's Human Rights Agency.

As the four-year-long stalemate in Aleppo reached its final, bloody climax, civilians in Aleppo posted heart-rending messages to the world on social media, saying they expected to die when forces loyal to the Syrian regime enter their areas.