The Iranian, Russian, and Turkish foreign ministers have met in southern Turkey to discuss the years-long civil war in Syria ahead of a summit between the three countries' presidents in Russia.
Turkish Foreign Minister Mevlut Cavusoglu met with his Russian counterpart, Sergei Lavrov, and Mohammad Javad Zarif of Iran in Antalya on November 19 for the closed-door talks.
Speaking after the meeting, Lavrov described the talks as "very useful," adding that the sides "reached agreement on all the key issues," according to Russian news agencies.
Russia's top diplomat declined to provide further details on the meeting.
He said the chiefs of the Iranian, Russian, and Turkish armed forces will also hold talks before Russia's President Vladimir Putin meets with his counterparts of Iran and Turkey -- Recep Tayyip Erdogan and Hassan Rohani – in the Black Sea resort city of Sochi on November 22.
The meeting will focus on reducing violence in Syria and matters related to the delivery of humanitarian aid to the region, officials said.
Moscow, Ankara, and Tehran are sponsoring separate talks in the Kazakh capital, Astana, that involve warring sides in the six-year civil war and focus on battlefield issues, such as the formation of de-escalation zones in key regions of Syria.
The United Nations is also sponsoring talks in Geneva that look to establish a political solution to the war.
Putin last met Erdogan in Sochi on November 13.
The Russian president said after the talks that Moscow and Ankara were "united in the need to increase efforts to ensure the long-term stabilization [of Syria], above all to advance the process of a political settlement."
"We agreed that there is now a base which allows us to focus on the political process," Erdogan said.
Russia and Iran have given crucial military backing to Syrian President Bashar al-Assad's government throughout the war, which began with a government crackdown on protesters and has killed more than 330,000 people, created 6.1 million refugees, and forced some 5 million people to become internally displaced.
Turkey supports rebels who want to oust Assad.