French president Emmanuel Macron is warning he would have a "real problem" if Turkey's campaign against Kurdish militia in Syria turns into an outright "invasion".
Turkey's President is considering expanding the offensive. He promised to sweep YPG fighters from the border. Ankara views them as terrorists and an extension of the outlawed Kurdistan Workers Party. But the US backs the Kurds - who've taken a leading role fighting the Islamic State. Some worry Turkey's campaign could lead to a confrontation with US troops.