The Syrian government and rebel groups have agreed a ceasefire and to begin peace talks, Russian President Vladimir Putin has announced.
The ceasefire is due to come into force at midnight (22:00 GMT) Thursday.
Turkish Foreign Minister Mevlut Cavusoglu said earlier that Turkey and Russia would act as guarantors under the plan.
The two countries back opposing sides in the conflict, which has raged for more than five years.
The truce does not apply to two of the main jihadist groups in Syria, so-called Islamic State and Jabhat Fateh al-Sham (formerly the Nusra Front), Turkish sources say.
But it reportedly does cover the rebel-held Eastern Ghouta area near Damascus, which had been a sticking-point in negotiations.
Earlier this month, Moscow and Ankara negotiated a ceasefire in Syria’s second city, Aleppo, that led to tens of thousands of rebel fighters and civilians being evacuated from an enclave besieged by government forces.
Previous ceasefire initiatives this year brokered by the UN, or the US acting with Russia, have quickly collapsed.
