Russian President Vladimir Putin spoke by telephone with the leaders of Turkey and Iraq about battle for Mosul, where Iraqi forces are fighting to oust the Islamic State group, the Kremlin said Wednesday.

Putin "wished the Iraqi army and its allies complete success in their objectives," the Kremlin said in a statement on his conversations with Turkish President Recep Tayyip Erdogan and Iraqi Prime Minister Haider al-Abadi.

He also informed the Iraqi leader about the "measures taken by Russia to defuse the situation" in the Syrian city of Aleppo.

Moscow announced on Tuesday that Russian and Syrian air forces had stopped bombing Aleppo ahead of an eight-hour "humanitarian pause" in the battered city on Thursday.

Putin is to attend a summit on Syria in Berlin later Wednesday with the leaders of France and Germany.

In a separate conversation, Putin also discussed the battle for Mosul with Erdogan, the Kremlin said, but gave no further details.

The long-awaited offensive against Iraq's second city began Monday with air and ground support from a US-led coalition.

Turkey said Tuesday it will continue to take part in the air operation after Ankara agreed a deal with its coalition partners.

Plans for the offensive were marked by tensions between Iraq and Turkey, which insisted on being part of the operation despite objections from Baghdad.