The International Atomic Energy Agency (IAEA) reported that Iran finished installing one of three new cascades of advanced IR-2m centrifuges at the underground portion of the Natanz nuclear complex and that the installation of the other two cascades is in progress. The IAEA also confirmed that Iran began enriching uranium in the newly installed cascade of 174 IR-2m centrifuges. A first cascade of IR-2m centrifuges began uranium enrichment at the underground facility last year. The 2015 nuclear accord restricts Iran to using only IR-1 centrifuges at this facility. Iran also said that it began installing advanced IR-6 centrifuges at the Fordow nuclear facility.