Iran's Foreign Ministry said talks in Vienna on reviving Tehran's landmark 2015 nuclear deal with world powers have made "significant progress," although there are still unresolved issues.
Under the deal known as the Joint Comprehensive Plan of Action (JCPOA), Tehran agreed to curb sensitive nuclear activities in exchange for sanctions relief.
Former President Donald Trump pulled the United States from that deal in 2018 and reimposed stringent sanctions that battered Iran's economy and its currency.
Since Washington's withdrawal from the deal, Iran has violated some of the its nuclear limits.
Talks with Iran to revive the deal have been taking place in Vienna since April and involve negotiators from Britain, China, France, Germany, and Russia. The United States is taking part indirectly, since Iran has refused to meet face-to-face with the American delegation.
Foreign Ministry spokesman Saeed Khatibzadeh said on February 21 significant progress was made, he also noted that "nothing is agreed until everything is agreed" in the Vienna talks. "The remaining issues are the hardest," he told a weekly press briefing.
Khatibzadeh said that Iran’s top security body, the Supreme National Security Council, handles the Vienna talks. It reports directly to Supreme Leader Ayatollah Ali Khamenei, Iran's ultimate authority.
The chief of the Supreme National Security Council, Ali Shamkhani, said separately on February 21 that talks with European negotiators were ongoing and would continue while negotiations with the United States were not on the agenda because they would not be the source of "any breakthroughs."