Iran has reversed a slowdown in the rate at which it is enriching uranium to up to 60 percent purity, close to weapons grade, returning to a rate of around 9 kg a month from the reduced rate of 3 kg, the International Atomic Energy Agency said on Tuesday.

"The IAEA confirmed that Iran had increased the production of UF6 (uranium hexafluoride) enriched up to 60% U-235 to approximately 9 kg per month since the end of November at these two facilities combined," the UN nuclear watchdog said in a statement, referring to sites at Fordow and Natanz.