Turkish President Recep Tayyip Erdogan said on Saturday that Ankara will carry out an air and ground military operation east of the Euphrates River in Syria "as soon as today or tomorrow". Speaking at the opening of his AK Partys annual camp, he said Turkey aimed to "water the east of Euphrates with fountains of peace" and settle refugees there. His remarks were the most direct indication of an incursion since Ankara and Washington decided to establish a "safe zone" in the area. "We gave all warnings to our interlocutors regarding the east of Euphrates and we have acted with sufficient patience," Erdogan said. The operation could start as soon as Saturday or Sunday, he said. NATO allies, Washington and Ankara, have agreed to establish a zone on the Syrian border that Turkey says should stretch 30 km (19 miles) into Syria and be cleared of the Syrian Kurdish People’s Protection Units (YPG), which it considers a terrorist organization. Turkey has accused the United States, which supports the YPG-led force that defeated ISIS in Syria, of moving too slowly to set up the zone. The two countries are also at odds over how far it should extend into Syria and who should control it Turkey says it wants to settle up to 2 million Syrian refugees in the zone, and has repeatedly warned of unilateral military action if it is not satisfied with progress. Turkey-backed Syrian opposition factions pledged on Friday to back a potential cross-border offensive that Ankara has threatened to mount against Kurdish fighters in northeast Syria. Turkey has twice launched military offensives with the factions in northern Syria in recent years. A Turkish military operation in northeastern Syria would carry a larger risk, bringing troops into a zone where at least 1,000 US soldiers are deployed.