The Portland, Oregon-based Mercy Corps said it was "seeking a dialogue" with Turkish authorities to resume operations that constitute one of the largest humanitarian operations for Syria.
It was the first time the men had met since 2015, weeks after Turkey's air force shot down a Russian jet at the Syrian-Turkish border. A US deployment and a Russian-brokered deal with Syrian forces created buffer zones that headed off any Turkish campaign against the Kurdish forces who hold the town - seen by Washington as key allies against Islamic State and by Turkey as terrorists.
McCain said a recent visit to Turkey and meeting with Erdogan impressed upon him how "passionately opposed" the Turkish president is to the Kurdish forces the United States is working with in Syria.
The pipeline will also increase Russia's leverage over Turkey which has nearly no gas storage facilities of its own and is entirely dependent on Russian Federation to deliver gas in exactly the amounts its requests from Moscow to run its economy.
"Mainly due to the active role of Russian Federation and Turkey, it became possible not only to achieve cessation of hostilities between the government forces and the opposition, but to start direct, concrete negotiations between the warring sides in Astana", he said.
Syria is now torn apart by warring factions, including the dictatorship of Bashar al-Assad, a variety of anti-Assad militias, the Kurdish People's Protection Unit (YPG/YPJ), the Islamic State, and Jabhat Fateh Al-Sham, the former Nusra Front.
Putin said the two countries had "great potential" for improving "good neighborly" relations.
Turkish President Recep Tayyip Erdogan vowed to keep strengthening cooperation between Russian Federation and Turkey despite differences on certain issues. The government forces and armed opposition groups, which have over 60,000 members, have joined the truce.
"Be it in Syria or in Iraq, in both countries our main objective is territorial integrity", said Erdogan.
The Turkish president further said Russian Federation, as a member of Minsk Group that is mediating between Azerbaijan and Armenia, can have an influential role in finding a solution on the Nagorno-Karabakh conflict between the two countries.
Moscow responded by barring the sales of package tours to Turkey and halting imports of agricultural products, moves that badly squeezed the Turkish economy.
Turkish president also said that he hopes that Russian Federation will remove all economic sanctions against Turkey. Erdogan only first appeared open to the idea of restoring ties with Russian Federation after the failed coup against him in July 2016.
During the Kremlin talks, he noted that plans for a prospective Russian natural-gas pipeline and a nuclear power plant in Turkey have also regained momentum. The focus of the meeting, which ended March 8, was "to strengthen the de-conflict mechanisms that we have already in place to ensure the safety and well-being of our various forces who are operating on the ground in Syria", he said.