Bangladesh, June 1 -- The Iranian foreign minister spoke by phone with the director of the UN's nuclear watchdog agency early Sunday morning after a report from the agency said Iran is further increasing its stockpile of uranium enriched to near weapons-grade levels.

Writing on Telegram, Abbas Araghchi said he stressed Iran's "continuous cooperation" in his conversation with Rafael Mariano Grossi, the head of the Vienna-based International Atomic Energy Agency.

The IAEA did not immediately return a request for comment about the phone call, reports AP.

The confidential IAEA report raised a stern warning, saying that Iran is now "the only non-nuclear-weapon state to produce such material" - something the agency said was of "serious conce...