Iran's foreign minister has suggested that the UN atomic agency is close to certifying that his country has met all commitments under its landmark nuclear deal with six world powers, as he began a series of meetings with his European Union and US counterparts on implementing the accord.
"All oppressive sanctions imposed against Iran will be annulled today," Mohammad Javad Zarif said in comments on Iranian state TV - a reference to the start of the process that will end financial and other penalties imposed on his country once the UN agency says Tehran has fulfilled its obligations to restrict its nuclear programmes.
Certification by the International Atomic Energy Agency would trigger sanctions relief worth an estimated £70 billion for Tehran.
Zarif and EU foreign policy chief Federica Mogherini, who met Saturday morning, were to be joined later by US secretary of state John Kerry in Vienna, headquarters of the IAEA.
Zarif said the deal between his country and the six world powers would hold, telling Iranian media that all parties would "not allow the outcome of these talks to be wasted".
Iran insists all of its nuclear activates are peaceful. But under the July 14 deal, Iran agreed to limit programmes it could use to make nuclear weapons in return for an end to sanctions.
The agreement puts Iran's various nuclear activities under IAEA watch for up to 15 years, with an option to re-impose sanctions should Tehran break its commitments.
The agreement, struck after decades of hostility, defused the likelihood of US or Israeli military action against Iran, something Zarif alluded to.
"Our region has been freed from the shadow of an unnecessary conflict that could have caused concerns for the region," he said. "Today is also a good day for the world. Today will prove that we can solve important problems through diplomacy."