Turkish President Recep Tayyip Erdogan today firmly ruled out any negotiations with Kurdish militants in Syria, saying their only option was to lay down arms and retreat.<br />''<br />'' He dismissed calls from foreign powers, including the United States, who have demanded a ceasefire in Turkey's week-old operation in northern Syria.<br />'' <br />'' Turkey launched Operation Peace Spring on October 9 with the aim of establishing what it calls a 'safe zone' across northern Syria, which would push back Kurdish fighters from the Turkish border and allow for the repatriation of Syrian refugees.<br />'' <br />'' President Erdogan said that once the safe zone was established, stretching from Manbij to the Iraqi border, then the operation would have ended on its own. <br />''  <br />