Russia making 'grave mistake' in Syria: Turkey's Erdogan

Moscow's bombing campaign in Syria is "unacceptable", Turkish President Recep Tayyip Erdogan said Sunday, warning that Russia was making a "grave mistake."

"The steps Russia is taking and the bombing campaign in Syria is unacceptable in any way... Unfortunately, Russia is making a grave mistake," Erdogan told a news conference at Istanbul airport before leaving for a visit to France.