The U.S. military’s unprecedented strikes on Iran’s nuclear facilities last month set back the country’s nuclear program by one to two years, according to top Defense Department spokesman Sean Parnell.

Parnell maintained during Wednesday’s Pentagon briefing that the U.S. strikes resulted in the “total obliteration of Iran’s nuclear ambitions,” which has been the Pentagon’s stance on the strikes since they occurred, though he added, “We have degraded their program by one to two years at least.”