North Korea must relinquish its nuclear program if it wants to achieve economic development and normalize diplomatic relations, the U.S. National Security Advisor said on Sunday.

Interviewed on CBS News’s “Face the Nation,” Robert O’Brien was asked what “signal” Pyongyang was aiming to send the world with a military meeting over the weekend at which the DPRK leader ordered officials to increase the country’s “nuclear war deterrence.”

In response, O’Brien said, the U.S. will continue monitoring and “keep talking” to the North.

“We’ll have to see,” he said. “But ultimately, the North Koreans, if they want to reenter the world,