U.S. Secretary of Defense Mark Esper on Wednesday appeared to express some reservations about the possibility that North Korea will fully denuclearize.

Speaking in an interview with Fox News, the recently-inaugurated Secretary of Defense was asked whether North Korean leader Kim Jong Un would ever relinquish his nuclear arsenal.

“Well, the experts will tell you probably not, but we’ll see,” he said, while drawing a parallel between prospects for the DPRK’s denuclearization and the collapse of the Soviet Union.

“Growing up in the 1970s and 1980s, I never thought we’d see the Soviet Union fall, but it did.”

Esper’s comments