His remark was not new as it was a repeat of similar warnings that other ranking North Korean officials previously made. But the report came at a delicate time when liberal politician Moon Jae-in was elected as South Korea's new president early Wednesday.

The Ministry of Unification said that it would be foolish if North Korea carries out another nuclear test at this juncture.

"Moon earlier warned that if North Korea conducts an additional nuclear test, everything including inter-Korean dialogue will not proceed," Lee Duk-haeng, ministry spokesman, told a regular press briefing.

On the campaign trail, Moon vowed to seek a dual-track approach of pushing denuclearization and dialogue with Pyongyang.

He earlier raised the need to resume the now-suspended joint industrial complex and a tour project at Mount Kumgang on the North's east coast, but he later struck a cautious note over hasty resumptions of the two projects.

"If North Korea comes to talks for denuclearization after freezing its nukes, we would be able to resume the Kaesong complex and the tour program," Moon told a forum in late April.

North Korea conducted two nuclear tests last year alone following those in 2006, 2009 and 2013, in defiance of international condemnation. (Yonhap)