Yet the final months of 2017 have been overshadowed by a series of air conversations and other threatening measures taken by Russian forces. According to the coalition, Russian and Syrian aircraft flew an average of six to eight times a day east of the Euphrates River, representing about 10 percent of all air activities, despite the November agreement. In one incident, a Russian Su-25 nearly collided with an F-22 coalition stealth fighter that had already intercepted the Russian jet after crossing the Euphrates River. The U.S. dilemma was clearly articulated by a coalition spokesperson: “It is becoming increasingly difficult for our pilots to know whether Russian pilots are deliberately testing or baiting us to react, or whether they are just honest mistakes. The biggest concern is that we could shoot down a Russian aircraft because its actions are considered a threat to our air or ground forces. On September 17, 2018, Russian President Vladimir Putin and Turkish President Recep Tayyip Erdogan agreed to create a buffer zone in Idlib. [103] After the Ghouta chemical attacks in August 2013, which drew international criticism of Syria`s chemical arsenal, the United States and Russia agreed on a framework for the elimination of Syrian chemical weapons. On 30 October 2015, the first round of peace talks on Syria with the foreign ministers of 20 participating countries: the United States, Russia, Iran, Saudi Arabia, Turkey, China, the United Kingdom, France, Italy, Germany and other countries. Ministers agreed that the Syrian government and the opposition should start political talks. [30] [31] The second round of the Viennese talks, in mid-November, resulted in an agreement on the need to bring together representatives of the Syrian government and the opposition for formal negotiations under the aegis of the United Nations, with a deadline of 1 January 2016. [32] The agreement would effectively preserve some of the territorial gains made by Russian-backed Syrian forces during a three-month offensive in Idlib, the country`s last rebel stronghold, while maintaining a Turkish foothold in the region. The talks ended without a final ceasefire agreement, supposedly due to the anti-government side`s refusal to accept new Russian conditions for control of Idlib province.

[110] As the U.S.-led campaign against the Islamic State progressed, deconfliction became increasingly relevant to ground operations. Starting in the spring of 2017, coalition-backed, pro-regime forces included in the Euphrates Valley. U.S. and Russian commanders were increasingly relying on geographical divisions to not endanger each other`s forces, first on an ad hoc basis in 2016, allegedly on the proposal of a Russian official, and then by a series of agreements reached in the summer of 2017. The conflict line largely followed the Euphrates South of tabqa city, with the US-backed Syrian Democratic Forces (SDF), claiming the area east of the river and deploying the Assad regime and its allies to the west.