The above-ground pilot enrichment plant at Iran's Natanz nuclear site has been destroyed, U.N. nuclear watchdog chief Rafael Grossi told a meeting of the U.N. Security Council on Friday on Israel's strikes on Iran.

Israeli defense officials believe damage to major facility is significant, while other enrichment facility at Fordo, nuclear sites in Isfahan, Busheir reportedly not targeted

Israel said it targeted Iran's oldest current enrichment site, Natanz, in its strikes. The site, secretly set up in 2002 but discovered soon after that, contains an underground fuel enrichment plant and a separate pilot fuel enrichment plant.