BERLIN (Reuters) - German Chancellor Angela Merkel urged Russia on Friday to use its influence with the Syrian government to end the devastating bombardment of Aleppo, as her government opened the door to possible sanctions against Russia for its role in the conflict.

In some of her harshest comments to date, Merkel said there was no basis in international law for bombing hospitals and Moscow should use its influence with Syrian President Bashar al-Assad to end the bombing of civilians.

“Russia has a lot of influence on Assad. We must end these atrocious crimes,” Merkel told party members in Magdeburg. She did not address sanctions directly, but said the international community needed to do all it could to bring about a halt in the fighting and get supplies to civilians.

Merkel’s chief spokesman Steffen Seibert, speaking at a regular news conference, declined to rule out possible sanctions against Russia for its part in the conflict, but said Berlin’s top priority remained a ceasefire to allow the delivery of humanitarian aid to the civilian population.

Seibert said Western officials discussed the Syrian conflict in Berlin on Wednesday and those discussions were continuing.

A foreign ministry spokesman told reporters on Wednesday that there were no formal proposals to impose sanctions on Russia over its role in Syria, but the issue has received growing attention in recent days.

ALEPPO FIGHTING

Syrian government forces backed by Russian air power have stepped up an offensive on rebel-held parts of the city of Aleppo in the most lethal bombardment in nearly six years of war, with conflict monitors citing attacks on hospitals and water supplies. Government forces fought fierce clashes with rebels in the south of the city on Friday.

Moscow and Damascus say they target only militants and deny they have bombed hospitals.

Norbert Roettgen, a member of Merkel’s Christian Democratic Union (CDU) and chair of the Foreign Affairs Committee in the German parliament, called for new sanctions against Russia over its role in the bombardment of Syria.

His comments to the Sueddeutsche Zeitung came two days after another CDU member and member of the European Parliament, Elmar Brok, urged the EU to impose new sanctions against Russia.

“A lack of consequences and sanctions for the most serious war crimes would be a scandal,” Roettgen said, adding military measures would be the wrong approach.

The idea of sanctions was discussed at a coalition meeting on Thursday and also at a meeting of senior officials from the United States, Britain, France, Italy and Germany in Berlin on Wednesday but both groups have decided against it for now, participants said.

Seibert urged key backers of the Assad regime, Russia and Iran, to use their influence to halt the escalation in violence and the suffering of the civilian population,” he said.

One European diplomat has said sanctions could prove extremely difficult for Europe.

The EU has sanctions in place against Moscow over the conflict in Ukraine. Italy and some other EU states have said these should be eased, but the prospects for any relaxation of those sanctions had dimmed, given the crisis in Syria.