Iran says it opposes the United States joining peace talks on Syria to be held in Kazakhstan next week.
That goes against the position of the other two organizers of the talks, Russia and Turkey, which have said the new U.S. administration of Donald Trump should be represented at the Astana talks, which begin on January 23.
"We have not invited them, and we are against their presence," Iranian Foreign Minister Mohammad Javad Zarif said on January 17, according to the Tasnim news agency.
"At this stage, we must keep the tripartite setup,” Iranian Foreign Ministry spokesman Bahram Ghasemi told AFP on January 18. "Any enlargement could increase the risk of failure."
Russia, Iran, and Turkey pushed for the peace talks after government forces won a major victory last month in retaking eastern Aleppo, a key rebel stronghold through much of the war.
Iran and Russia have been key backers of Syrian President Bashar al-Assad in the conflict, while Turkey supports rebel groups.