The UN nuclear watchdog's Director General Rafael Mariano Grossi will meet with senior Iranian officials in Tehran to discuss the stockpile that the group says can easily be used for atomic weapons.
Iran's stockpile of enriched uranium has reached more than 15 times the limit set out in the 2015 accord between Tehran and world powers.
In a new report by the UN nuclear watchdog International Atomic Energy Agency (IAEA), seen by AFP news agency on Thursday, the estimated stockpile now stands at 3,197.1 kilograms.
The limit in the 2015 deal was set at 300 kilograms (660 pounds) of enriched uranium.
Such highly enriched uranium can be easily refined to make atomic weapons, which is why world powers have sought to contain Tehran’s nuclear program.
The Vienna-based agency told members that it is still not able to verify Iran’s exact stockpile of enriched uranium due to the limitations that Tehran imposed on UN inspectors last year.
The IAEA announced earlier that Director General Rafael Mariano Grossi will travel to Tehran for meetings with senior Iranian officials on Saturday.
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In a report to member states about its work in Iran, the agency said it estimates that as of February 19, Iran’s total enriched uranium stockpile was 3,197.1 kilograms, an increase of 707.4 kilograms.
Senior diplomats from Britain, China, France, Germany and Russia have been meeting with Iranian officials in Vienna since November to discuss bringing Tehran back into compliance with the 2015 Joint Comprehensive Plan of Action.
The pact eased sanctions on Iran in return for curbs on its nuclear program.
The United States pulled out of the accord under former President Donald Trump and reimposed sanctions on Iran, prompting Tehran to resume its uranium enrichment.
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