It's the extra protocol to inspect non-nuclear sites that Iran rescinded. And why wouldn't they? Having them didn't benefit Iran in any way. None of their IAEA partners would agree to those protocols either.
U.S. says it killed 10 AQAP Islamist militants in four air strikes in Yemen since April 23 (Reuters)
from the article: 'Major powers to ease sanctions if Iran shuts down Fordow nuclear plant'