Iran and the United States, France, Germany, Britain, China and Russia will reconvene in Vienna on Tuesday to try to iron out differences over how to end a long standoff over suspicions that Tehran has sought the means to develop nuclear weapons. In a sign that something might be in the works, Russian Foreign Minister Sergei Lavrov arrived in Vienna and Chinese Foreign Minister Wang Yi was due on Sunday, but the schedule for ministerial talks was unclear. The senior Iranian official in Vienna said Iran would sign up to a special IAEA inspection regime called the Additional Protocol, which would be provisionally implemented at the start of a deal and, eventually, ratified by Iran's parliament. While missiles are not at the heart of the talks over Iran's nuclear work, which centre on the production of fissile material usable in atomic bombs, Western countries would like them discussed at the nuclear discussions. The Protocol allows IAEA inspectors increased access to sites where they suspect nuclear activity is taking place, but U.S. officials say it is insufficient because it could allow Iran to stall by dragging out negotiations over access requests. The United States has said that sanctions removal on Iran will be phased gradually, but Iranian officials, including Supreme Leader Ali Khamenei, have said that sanctions on Iran must be lifted as soon as a final agreement is concluded.
Tasnim News Agency reports that, in a Nowruz speech, Supreme Leader of Iran Ali Khamenei said experts in his country can enrich uranium to 99 percent. ISNA reports that Iranian Foreign Minister Mohammad Javad Zarif is threatening to quit the Iran nuclear deal if the United States blocks Iran's version of the deal's implementation.