Russian President Vladimir Putin said that his country has no other option but to clear what he called "a terrorist nest" from Aleppo, despite the fact that civilians are still present in the city.

"Bells should toll for all innocent victims. I agree with you. We hear all the time 'Aleppo, Aleppo, Aleppo.' The question is: we either leave a terrorist nest there or do everything possible to minimise, to avoid civilian casualties, to clear it out," Putin said.

Putin also said civilian casualties in conflict zones everywhere should be mourned, not just in Aleppo. He pointed to civilians killed near Mosul in Iraq. He added that Russia was showing restraint in Syria, but might lose patience and respond in some way to unspecified actions.