Merkel threatens sanctions over Aleppo

The European Union will impose sanctions on Syria and Russia if the "barbaric" bombing of Aleppo continues, German Chancellor Angela Merkel says.

The German chancellor has demanded an end to attacks by Syrian and Russian forces on Aleppo. (AAP)

German Chancellor Angela Merkel has demanded an end to attacks by Syrian and Russian forces on the northern city of Aleppo, saying the European Union will take measures against both if the "barbaric" campaign continues.

"We demand an end to the attacks. We have not only said that we could not only impose sanctions against Syria but also sanctions against all who are allied with Syria. This applies to Russia," Merkel said in Brussels on Friday.

EU leaders condemned Russia for its bombing of civilians in the besieged city of Aleppo but faced resistance from Italy to impose new sanctions against Moscow over the atrocities.