The UN and Arab League's envoy to mediate the Syria conflict, Kofi Annan, will visit Tehran next week, Iranian Foreign Minister Ali Akbar Salehi said on Wednesday.

"Kofi Annan is probably coming to Tehran on Monday," Salehi told reporters on the sideline of a visit by Turkish Prime Minister Recep Tayyip Erdogan.

The foreign minister also said "there are some differences between Iran and Turkey vis a vis the issue of Syria."

"But we are nearing to closing the gap of differences with the mission of Mr Kofi Annan and with the support of Turkey, Arab nations and the UN we hope there will be a way out for the Syrian issue," he said, speaking to reporters in English.

Iran is Syria's chief ally in the Middle East, and has provided the regime of Syrian President Bashar al-Assad with political and material support as it cracks down on an uprising.

Assad has reportedly accepted a six-point plan put forward by Annan that calls for a daily two-hour humanitarian ceasefire and access to all areas affected by the fighting in Syria.

Annan has in the past few days held talks with the leaders of Syria's two other key allies, China and Russia.