Turkish President Recep Tayyip Erdogan makes statements in Istanbul, Turkey, on April 16, 2017. Turkish President Recep TayyipErdogan declared on Sunday night that the proposed constitutional changes were accepted in a referendum, paying the way for the country to introduce the presidential system. (Xinhua photo)

ISTANBUL, April 28 (Xinhua) -- Turkish President Recep Tayyip Erdogan on Friday urged coalition forces and the United States to clear the Islamic State (IS) elements from Syria's northern towns of Manbij and Raqqa.

"Together with the coalition led by the United States, Turkey and the Free Syrian Army can clean the area all together," Erdogan said at a meeting in Istanbul hosted by the U.S.-based Atlantic Council think tank.

Currently there should be around 2,500 to 5,000 terrorists in the IS stronghold of Raqqa, the president said. "It is not difficult for us," he remarked. "Why do we exist if we cannot succeed?"

Turkey has suggested a joint operation to retake Raqqa on condition that the United States keeps away the Syrian Kurdish fighters, who are seen by Ankara as the Syrian offshoot of the outlawed Kurdistan Workers' Party but treated by the United States as a reliable ground force against the IS.

Backed by the rebel Free Syrian Army, the Turkish military launched an operation in northern Syria in August last year and managed to clean an area of some 2,500 square kilometers. Turkish troops' move against Kurds-held Manbij, however, was blocked by the United States and Russia.

"We should hand over Manbij to Arabs, who are its real owners," Erdogan said.