Iran is prepared to ramp up its uranium enrichment capabilities as the U.S. continues nuclear deal negotiations in Vienna, according to a United Nations watchdog.

A report from the U.N.’s International Atomic Energy Agency (IAEA) Monday found that Iran is preparing to install IR-6 centrifuges at its underground Fordow facility, according to Reuters. The machines can allow Iran to enrich uranium to 20% purity and potentially more.