Vienna — Iran has further increased its stockpile of uranium enriched to near weapons-grade levels, according to a confidential report on Monday by the United Nations’ nuclear watchdog, the latest in Tehran’s attempts to steadily exert pressure on the international community.

Iran is seeking to have economic sanctions imposed over the country’s controversial nuclear program lifted in exchange for slowing the program down. The program – as all matters of state in Iran – are under the guidance of Iran’s supreme leader, Ayatollah Ali Khamenei, and that likely won’t change in the wake of last week’s helicopter crash that killed Iran’s president and foreign minister.

The report by the International Atomic Energy Agency also comes against the backdrop of heightened tensions in the wider Middle East over the ongoing Israel-Hamas war. Israel and Iran have carried out direct strikes on each other’s territory for the first time last month.

The report, seen by several news agencies, said that as of May 11, Iran has 142.1 kilograms (313.2 pounds) of uranium enriched up to 60% – an increase of 20.6 kilograms (45.4 pounds) since the last report by the U.N. watchdog in February. Uranium enriched at 60% purity is just a short, technical step away from weapons-grade levels of 90%.

By IAEA’s definition, around 42 kilograms (92.5 pounds) of uranium enriched to 60% is the amount at which creating one atomic weapon is theoretically possible – if the material is enriched further, to 90%.

Also as of May 11, the report says Iran’s overall stockpile of enriched uranium stands at 6,201.3 kilograms (1,3671.5 pounds), which represents an increase of 675.8 kilograms (1,489.8 pounds) since the IAEA’s previous report.

Iran has maintained its nuclear program is for peaceful purposes only, but the IAEA chief, Rafael Mariano Grossi, has previously warned that Tehran has enough uranium enriched to near-weapons-grade levels to make “several” nuclear bombs if it chose to do so. He has acknowledged the U.N. agency cannot guarantee that none of Iran’s centrifuges may have been peeled away for clandestine enrichment.

Iran’s continuing lack of transparency on its nuclear program

Tensions have grown between Iran and the IAEA since 2018, when then-President Donald Trump unilaterally withdrew the United States from Tehran’s nuclear deal with world powers. Since then, Iran has abandoned all limits the deal put on its program and quickly stepped up enrichment.

Under the original nuclear deal, struck in 2015, Iran was allowed to enrich uranium only up to 3.67% purity, maintain a stockpile of about 300 kilograms and use only very basic IR-1 centrifuges – machines that spin uranium gas at high speed for enrichment purposes.

The 2015 deal saw Tehran agree to limit enrichment of uranium to levels necessary for generating nuclear power in exchange for the lifting of economic sanctions. At the time, U.N. inspectors were tasked with monitoring the program.

Monday’s report also said Tehran hasn’t reconsidered its September 2023 decision to bar IAEA inspectors from further monitoring its nuclear program and added that it expects Iran “to do so in the context of the ongoing consultations between the (IAEA) agency and Iran.”

According to the report, Grossi “deeply regrets” Iran’s decision to bar inspectors – and a reversal of that decision “remains essential to fully allow the agency to conduct its verification activities in Iran effectively.”

The deaths of Iran’s President Ebrahim Raisi and Foreign Minister Hossein Amirabdollahian have triggered a pause in the IAEA’s talks with Tehran over improving cooperation, the report acknowledged.

Before the May 19 helicopter crash, Iran had agreed to hold technical negotiations with IAEA on May 20, following a visit by Grossi earlier in the month. But those meetings fell apart due to the crash. Iran then sent a letter on May 21 saying its nuclear team wants to continue discussions in Tehran “on an appropriate date that will be mutually agreed upon,” the report said.

The report also said Iran still hasn’t provided answers to the IAEA’s years-long investigation about the origin and current location of manmade uranium particles found at two locations that Tehran has failed to declare as potential nuclear sites, Varamin and Turquzabad.

It said the IAEA’s request needs to be resolved, or the the agency “will not be able to confirm the correctness an completeness of Iran’s declarations” under a safeguards agreement between Tehran and the nuclear watchdog.

The report also said there was no progress so far in reinstalling more monitoring equipment, including cameras, removed in June 2022. Since then, the only recorded data is that of IAEA cameras installed at a centrifuge workshop in the city of Isfahan in May 2023 – although Iran hasn’t provided the IAEA with access to this data.

The IAEA said that on May 21, IAEA inspectors, after a delay in April, “successfully serviced the cameras at the workshops in Isfahan and the data they had collected since late December 2023 were placed under separate Agency seals and Iranians seals at the locations.”