"The Syrian government welcomes the closing statement" of the meeting in the Black Sea resort of Sochi, said a foreign ministry source quoted by the official SANA news agency.
The leaders of Iran and Turkey on Wednesday supported the convocation of a Syrian peoples' congress as one of the first steps to establish inclusive dialogue in the war-ravaged country, Russian President Vladimir Putin said on Wednesday.
Syria's government has welcomed the joint declaration of the tripartite summit between the presidents of Russia, Iran and Turkey held on Wednesday in Russia's Sochi, an official source at the Ministry of Foreign Affairs and Expatriates said.
The congress would "gather representatives of different political parties, internal and external opposition" to discuss "the parameters of the future state", Putin said, adding that it would be "a stimulus for activating the efforts for Syria regulation in the framework of the Geneva process".
"The presidents of the three countries emphasised the establishment of peace and stability, unity and territorial integrity in Syria and will continue their cooperation until the end of terrorism in the region", he continued.
"The participants stressed that this (the transition) can not happen without the departure of Bashar al Assad and his clique at the start of the interim period", opposition groups said in a communique at the end of a meeting in Saudi Arabia.
Turkey also emphasized at the Sochi meeting, Unal said, that there must be negotiations between Assad and the opposition, which Ankara has supported from the start of Syria's civil war, now in its seventh year.
Even though Russian Federation and Iran have backed Assad's government since the start of the Syrian conflict in March 2011, while Turkey has supported his foes, the three countries have teamed up to help mediate a peace settlement.
The United Nations' Syria envoy says he plans to host two rounds of peace talks in Geneva next month between President Bashar Assad's government and the weakened opposition.