MOSCOW, May 10. /TASS/. Assisting in efforts for a safe return home of Syrian refugees has been one of the key principles for Moscow, Damascus, Ankara and Tehran, Russia’s top diplomat Sergey Lavrov said on Wednesday.

"It has been a key principle for all the countries present here to contribute to a safe and voluntary return of refugees and internally displaced persons to the places of their permanent residence in Syria as well as to ensure their right to receive support," Lavrov said, opening negotiations on Syrian settlement with his counterparts from Syria, Turkey and Iran.

Moscow is hosting a meeting of the four foreign ministers on Wednesday.

Relations between Ankara and Damascus soured after the conflict began in Syria in 2011, when flows of Syrian refugees flooded Turkey. Diplomatic ties between the two countries were severed then.