DUBAI, United Arab Emirates — The Iranian Foreign Minister spoke by phone with the director of the U.N.’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.

On Telegram, Abbas Araghchi said he stressed Iran’s “continuous cooperation” in his conversation with Rafael Mariano Grossi, head of the Vienna-based International Atomic Energy Agency. The IAEA did not immediately return a request for comment about the call.

The confidential IAEA report, which was seen by the Associated Press on Saturday, 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 concern.”

The IAEA said in a separate report that Iran’s cooperation with the agency has been “less than satisfactory” when it comes to uranium traces discovered by IAEA inspectors at several locations in Iran that Tehran has failed to declare as nuclear sites.

— The Associated Press