The head of the U.N. nuclear watchdog agency says Iran has not provided additional details about the discovery of uranium particles of man-made origin at a location that had not been declared.

Cornel Feruta, the acting director of the International Atomic Energy Agency, told its board of governors Thursday that a meeting in Tehran was planned for next week to discuss the issue.

Feruta reported to IAEA member states two weeks ago that his inspectors had confirmed traces of uranium "at a location in Iran not declared to the agency," which appeared to confirm allegations made by the U.S. and Israel about a secret nuclear warehouse.

Iran's Ambassador to the International Atomic Energy Agency, IAEA, Gharib Abadi, waits for the start of the IAEA board of governors meeting at the International Center in Vienna, Austria, Thursday, Nov. 21, 2019. (AP PhotoRonald Zak)

Iran's Ambassador to the International Atomic Energy Agency, IAEA, Gharib Abadi, waits for the start of the IAEA board of governors meeting at the International Center in Vienna, Austria, Thursday, Nov. 21, 2019. (AP PhotoRonald Zak)

Feruta says “it is essential that Iran works with the agency to resolve this matter promptly.”