Iran has started enriching uranium with a third cascade, or cluster, of advanced IR-2m centrifuges at its Natanz nuclear facility, the International Atomic Energy Agency (IAEA) tells its members.

"On 7 March 2021, the Agency verified ... that: Iran had begun feeding natural UF6 into the third cascade of 174 IR-2m centrifuges," the UN nuclear agency said in a Monday report obtained by Reuters, referring to uranium hexafluoride, the feedstock for centrifuges.

"The fourth cascade of 174 IR-2m centrifuges was installed but had yet to be fed with natural UF6; installation of a fifth cascade of IR-2m centrifuges was ongoing; and installation of a sixth cascade of IR-2m centrifuges had yet to begin," it added.

Iran’s representative to the Vienna-based organizations said in February that the country had installed new cascades of advanced centrifuges at two nuclear sites in Natanz and Fordow to increase enrichment capacity.