President Recep Tayyip Erdoğan on Tuesday said that the allies are moving toward the idea of forming a 'ISIS-free zone' in northern Syria as he said there were positive developments in this regard. Responding to questions asked by reporters in Antalya, president Erdoğan said that efforts in train-and-equip continues, while adding that the allies are starting to agree on a 'terror-free zone' in northern Syria. Erdoğan also said that there were positive developments regarding the establishment of an ISIS-free zone and a ground operation in Syria.Referring to the Incirlik air base in Adana province that is being used by U.S. warplanes to attack ISIS targets, Erdoğan added: "If it is necessary, they can use also other air bases against ISIS. We are determined to fight against the group."Turkey stepped up its campaign against the terrorist group in July when it carried out its first airstrikes in Syria. Since then, ISIS has carried out suicide bomb attacks in Turkey that have resulted in more than 130 deaths, including the October attack in Ankara.Erdoğan revealed he had a 45-minute phone call with U.S. President Barrack Obama on Monday to discuss the civil war in Syria.The Turkish president underscored the country's sensitivity with regards to the PKK's Syrian offshoot, the Democratic Union Party's (PYD) attempt to cross the Euphrates River to reach Jarablus and reiterated once again that Turkey will take the necessary measures to secure its borders. "Turkey will not let anybody cross the west of Eupharates from Syria" he said."There are steps that Turkey has taken and will take against all terrorist organizations especially ISIS, which poses a threat to Turkey" Erdoğan added. He also criticized Russia for conducting airstrikes against non-ISIS targets. "The attitude of the coalition forces is really important," he said. and added that "To strike civilians or the Turkmens in Syria in the guise of striking ISIS is not tolerable."In October, the Turkish military retaliated against PYD's attempt to cross the Euphrates to reach Jarablus and Turkish officials have said that Turkey does not need anybody's permission to protect its borders.