The UN’s nuclear watchdog estimates that Iran's stockpile of enriched uranium has grown to more than 18 times the limit laid down in the 2015 nuclear deal between Iran and world powers.
The International Atomic Energy Agency (IAEA) report on May 30 also says that Iran is continuing its enrichment of uranium to levels higher than the 3.67 percent limit in the deal.
The stockpile of uranium enriched up to 20 percent is now estimated to be 238.4 kilograms, up 56.3 kilograms since the last report in March. The amount of uranium enriched to 60 percent stands at 43.1 kilograms, an increase of nearly 10 kilograms.
That amounts to more than what the IAEA calls a "significant quantity," defined as "the approximate amount of nuclear material for which the possibility of manufacturing a nuclear explosive device cannot be excluded."
Enrichment levels of around 90 percent are required for use in a nuclear weapon.
Western powers say Iran is getting closer to being able to quickly produce a nuclear bomb if it chose to, though Tehran insists its nuclear program is peaceful.
The latest report comes as talks to revive the landmark 2015 nuclear deal between Iran and world powers remain deadlocked.
Then-U.S. President Donald Trump withdrew from the accord in 2018 and reimposed harsh economic sanctions. Talks to revive the agreement resumed in Vienna last year but have stalled. The U.S. special envoy for Iran said last week that the prospects of reviving the deal are “tenuous” at best.
In a separate report on May 30, the IAEA said Iran has done little to answer the nuclear agency's long-standing questions on the origin of uranium particles found at three undeclared sites.
"Iran has not provided explanations that are technically credible in relation to the Agency's findings at those locations," according to the report, quoted by Reuters. "The safeguards issues related to these three locations remain outstanding."
The lack of progress could set up a new diplomatic clash when the IAEA’s Board of Governors meets next week. If Western powers seek a resolution criticizing Tehran, it could deal a further blow to stalled efforts to revive the nuclear deal.