Iran stands poised to “quite dramatically” increase its stockpile of near weapons-grade uranium as it has started cascades of advanced centrifuges, the head of the International Atomic Energy Agency warned Friday.

The comments from Rafael Mariano Grossi came just hours after Iran said it conducted a successful space launch with its heaviest payload ever, the latest for its program that the West alleges improves Tehran’s ballistic missile program.

The launch of the Simorgh rocket comes as Iran’s nuclear program now enriches uranium at 60%, a short, technical step from weapons-grade levels of 90%. While Iran maintains its program is peaceful, officials in the Islamic Republic increasingly threaten to potentially seek the bomb and an intercontinental ballistic missile that would allow Tehran to use the weapon against distant foes like the United States.