United Nations-Arab League mediator Lakhdar Brahimi on Sunday visited Syria's close ally Iran to try to break a deadlock in political talks aimed at ending Syria's three-year war.
Brahimi met Ali Shamkhani, Secretary of Iran's Supreme National Security Council, shortly after his arrival in Tehran.
The Syrian peace talks led Brahimi in Geneva ended in February without progress and the UN hopes that Iran as a major country in the region could play an important role in urging the Syrian government to come to future talks in "a more constructive way."
Iran has supplied Syrian President Bashar Assad with cash, weapons and Shiite fighters linked to Hezbollah, and UN Secretary-General Ban Ki-moon was forced to rescind his last-minute invitation to Tehran to attend the January 23 opening of the last round of peace talks in Geneva, under pressure from the US and the Syrian opposition.
Brahimi last visited Iran in late October.
Also on Sunday, Iran's foreign minister said his country did not expect to cement a final deal in the coming round of nuclear talks with world powers.
Mohammad Javad Zarif spoke to reporters after meeting his Belarusian visiting counterpart, Vladimir Makei.
"We don't expect to reach a deal in this round of talks. Nor was a deal on the agenda for this round of talks. We have agreed to discuss a number of issues in this round,"
Zarif said.
Zarif said Tehran and world powers will discuss "dimensions" of Iran's nuclear activities like uranium enrichment, a heavy water reactor as well as sanctions in the Tuesday and Wednesday talks in Vienna.
"We will also discuss international cooperation in the field of peaceful nuclear technology," Zarif said.
Iran capped uranium enrichment after a deal in November for a six-month period, in return for easing sanctions by the West.
That interim agreement is meant to lead to a final accord that minimises any potential Iranian nuclear weapons threat in return for a full lifting of sanctions.
Also in Tehran on Sunday, Greek Foreign Minister Evangelos Venizelos met Iranian President Hassan Rouhani.
Venizelos held talks with Zarif on Saturday and has urged the US to adopt a realistic approach towards Iran's nuclear programme.
Greece holds the presidency of the European Union in the first half of 2014.
AP