The UN nuclear watchdog said Monday that it estimated Iran's stockpile of enriched uranium had grown to more than 18 times the limit laid down in Tehran's 2015 deal with world powers.

The International Atomic Energy Agency said in its latest report on Iran's nuclear programme that it "estimated that, as of May 15, 2022, Iran's total enriched stockpile was 3,809.3 kilograms." 

The limit in the 2015 deal was set at 300 kg (660 pounds) of a specific compound, the equivalent of 202.8 kg of uranium.

The report 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 kg, up 56.3 kg since the last report in March, while the amount enriched to 60 percent stands at 43.1 kg, an increase of 9.9 kg. 

Enrichment levels of around 90 percent are required for use in a nuclear weapon.

Iran has always insisted its nuclear programme is peaceful.

The latest report comes as talks to revive the landmark 2015 nuclear deal between Iran and world powers remain deadlocked after stalling in March.