UN peace envoy Staffan de Mistura met with Syrian Foreign Minister Walid Muallem on Sunday in Damascus to discuss ongoing international talks on Syria's four-year war, state media said.

The diplomat presented Muallem with a "detailed report" of talks between global powers as well as the United Nations and the European Union last week in Vienna, state news agency SANA reported.

Syria's state television said Muallem had "expressed to... de Mistura the importance of numerous points" in the statement released at the end of the Vienna talks.

But the Syrian foreign minister said he was "surprised that the statement did not include a commitment by known backers of terrorism" to stop supporting extremist groups, SANA reported.

Representatives from the UN and EU and top diplomats from 17 countries gathered on Friday in Vienna to narrow their divisions over the war which has killed more than 250,000 people.

For the first time, the meeting brought together all the main outside players in the crisis, including Russia and Iran, key allies of the government of President Bashar al-Assad.

But the Syrian government and the opposition were not represented.

Participants at the talks agreed to ask the United Nations to broker a peace deal between the regime and opposition to clear the way for a new constitution and UN-supervised elections.

But divisions remained on the fate of Assad, with Russia and Iran resisting Western and Saudi pressure to force the Syrian president from power.

De Mistura was expected to leave Damascus on Monday, the UN official said, declining to provide further details on the diplomat's visit.

He last visited Damascus in September to discuss his proposal for joint working committees to discuss counterterrorism, political and legal issues, reconstruction, and safety and protection.