Song Min-soon, the Deputy Minister of Foreign Affairs and Trade, said on Monday that the government is closely following developments in North Korea's possible nuclear tests, and there has been no indication yet supporting the plausibility of such tests.

Last month, North Korea shut down a nuclear reactor in Yongbyon in what experts believe was a preparatory step to extracting weapons-grade plutonium.

Citing unnamed diplomats, the Associated Press recently reported that US officials warned allies on Saturday that satellite imagery suggested an upcoming North Korean nuclear test possibly as early as June.

On whether the US actually notified the government of the possible test, Song flatly denied that there was any such notice from Washington.

He added that a missile recently fired by Pyongyang was a short-range weapon with only a 100-kilometer range, and that it had nothing to do with nuclear weapons.