However, another formal document exists between the two countries: the Joint Cooperation Agreement on Counter-Terrorism and Terrorist Organizations, signed on 21 December 2010 by Turkish Foreign Minister Ahmet Davutoglu and his Syrian counterpart Walid Muallem, in support of the Adana Agreement. The 23-article agreement came into force on 26 April 2011, after approval by the government and Parliament, replacing the Adana agreement. The agreement had a three-year validity period, which was automatically renewed, unless both sides withdrew, but with the outbreak of the Syrian conflict, it became irrelevant. In addition, Turkey`s border policy has allowed the passage of weapons and militants into Syria and has encouraged the insurgency. From Damascus` point of view, it is Turkey that has flagrantly violated the agreement over the past eight years. In a speech to the Turkish Military Academy on Thursday, Erdogan hinted that the Russian proposal could work: "[The Adana agreement] was based on the handover of the separatist terrorist organization to us. The fact that the agreement was reached during our discussions with President Putin helps us to better understand that we need to emphasize. The Adana agreement also provided for Turkey and Syria to enter into a reciprocal agreement in which they abstained from any military activity that would jeopardize the security of the other. Russia proposes that the agreement, if fully implemented, could resolve one of the most difficult differences in the Syrian conflict - the status of the YPG. Syria`s decision to expel Ocalan and negotiate with Turkey was linked to its concern about the strength of the Turkish army in the face of its own weakness.

However, a few years later, Syrian President Bashar Assad said in an interview that "the deportation of Ocalan was not out of fear, but because we preferred you. We could either be friends with the Turkish people, or prefer the Kurds and lose you. As our preference was with you, we sent Ocalan. In signing the agreement, Syria recognized the PKK as a terrorist organization and pledged not to provide financial, logistical or military support. Until 2011, Turkey benefited greatly from the agreement in its fight against the PKK. However, when the civil war broke out in Syria, Assad was inclined to replay the PKK`s map against Turkey because his northern neighbour had taken a hard stance and criticized him. Article 1 of the Adana Agreement states that "on the basis of the principle of reciprocity, Syria will not allow any activity that originates from its territory and that would compromise Turkey`s security and stability." However, several reports during the war suggested that Syria had given the PKK carte blanche on its soil and that the Syrian security services had murdered moderate Kurdish politicians to allow the PKK to re-assert itself in kurdish areas.