Iran's progress toward having a nuclear weapon is central to the current conflict between Israel and Iran. Before launching recent attacks against Iran's nuclear sites, Israel said it had evidence Tehran was on the brink of building a nuclear weapon.

With Donald Trump mulling whether to send in American bunker-busting bombs to deal a crushing blow to Iran’s nuclear facilities, doubts remain about just how close Iran is to creating a nuclear bomb.

Much of the world views Iran’s nuclear program with alarm, and experts say its stockpile of highly enriched uranium has grown fast.