What does the IAEA know about Iran’s stockpile of highly enriched uranium?

Rafael Grossi has served as the director general of the International Atomic Energy Agency, the United Nations’ nuclear watchdog, since 2019. Prior to that, Grossi held various positions related to nuclear safety and the non-proliferation of nuclear weapons. A veteran diplomat, he was also Argentina’s ambassador to Austria and the Argentine Representative to the IAEA and other international organizations. This journalism is made possible by viewers like you. Donate to FRONTLINE now: https://bit.ly/47DFzCb And support your local PBS station here: https://www.pbs.org/donate Grossi spoke to FRONTLINE’s Sebastian Walker on March 18 for our 2026 update of the documentary, “Strike on Iran: The Nuclear Question.” This interview has been edited for length and clarity. See a more complete description of our process here: https://to.pbs.org/4lVZKzA This interview is being published as part of FRONTLINE’s Transparency Project, an effort to open up the source material behind our documentaries. Read more about this project here: https://www.pbs.org/wgbh/frontline/ab... “Strike on Iran: The Nuclear Question” is available to watch here:    • Strike on Iran: The Nuclear Question (upda...   Explore more of our extended interviews in this playlist:    • The FRONTLINE Interviews   #Iran #NuclearProgram #IAEA Subscribe on YouTube:    / pbsfrontline   Sign up for our newsletter: https://frontline.org/newsletter Instagram:   / frontlinepbs   Facebook:   / frontline   Bluesky: https://bsky.app/profile/frontlinepbs... FRONTLINE is produced at GBH in Boston and airs nationwide on PBS. The editor-in-chief and executive producer of FRONTLINE is Raney Aronson-Rath. Funding for FRONTLINE is provided through the support of PBS viewers and by the Corporation for Public Broadcasting, with major support from Ford Foundation, and The Fialkow Family Foundation, as part of the Plum Bush Foundation. Additional support for FRONTLINE is provided by the Abrams Foundation, Park Foundation, John D. and Catherine T. MacArthur Foundation, Heising-Simons Foundation, and the FRONTLINE Trust, with major support from Jon and Jo Ann Hagler on behalf of the Jon L. Hagler Foundation, and Corey David Sauer, and additional support from Koo and Patricia Yuen.