Russian Foreign Minister Sergei Lavrov has stressed Iran’s influential role in settling the Syria unrest, underlining the need for the inclusion of Iran in an upcoming international conference on Syria.

“If we admit that Iran has a very solid influence on what is going on, then it is obliged to be represented in the negotiations as a participant in the ‘external ring’ [of Syria's neighboring states],” Lavrov said on Sunday.

At a joint press conference in Moscow on May 7, the Russian foreign minister and US Secretary of State John Kerry agreed to encourage the Syrian government and the foreign-backed militants to find a political solution to the crisis.

Moscow and Washington also agreed to hold an “international peace conference” on Syria in Geneva, which will serve as a follow-up to an earlier Geneva meeting in June 2012.

The Russian foreign minister stated that the duration of the forthcoming conference should not be limited.

    “Some of our partners…think a few days or weeks are long enough. I consider this is counterproductive,” he said.

Syria unrest erupted over two years ago and many people, including large numbers of Syrian soldiers and security personnel, have been killed in the violence.

Several international human rights organizations say the foreign-backed militants have committed war crimes in Syria.