MOSCOW, May 27. /TASS/. Presidents of Russia and Turkey, Vladimir Putin and Recep Tayiip Erdogan in a telephone conversation on Saturday agreed to step up efforts towards a settlement in Syria at various levels, the Kremlin's press service said.

"During the discussion of the Syrian crisis, they stressed the importance of an earliest accord on practical aspects for implementing the Memorandum on the de-escalation zones in the Syrian Arab Republic," the press service said. "Thus, it would be possible to reinforce the ceasefire, and boost the effectiveness of the intra-Syria talks in the Geneva and Astana formats."

"The parties agreed to step up coordinating efforts on this topic at various levels," the Kremlin said.

The leaders exchanged greetings on the 25th anniversary of the Treaty on the Principles of Relations between the Republic of Turkey and the Russian Federation," signed on May 25, 1992. Putin wished Erdogan success, who had been elected leader of the Justice and Development Party.

The heads of state "confirmed their aspirations to further develop their strategic partnership," the Kremlin’s press service said. "They touched on the agreements to mutually lift trade restrictions and carry out major joint construction projects, mainly the Akkuyu NPP and the Turkish Stream gas pipeline."