South Korea’s Defense Ministry has expressed doubt over North Korea's ability to miniaturize nuclear weapons to mount them on a ballistic missile.

Defense Ministry spokesman Kim Min-seok said during a regular press briefing on Friday that the South Korean military believes Pyongyang has not yet been able to make nuclear weapons small enough.

The assessment by South Korean military authorities differs from the United States’ belief that North Korea already holds nuclear weapons that can be loaded on a ballistic missile.

The Defense Intelligence Agency said it believes with moderate confidence that the North currently has nuclear weapons capable of delivery by ballistic missiles.