North Korea slammed the United States on Thursday for meddling in inter-Korean affairs after Washington voiced disappointment over Pyongyang's decision to cut off all communication lines with South Korea.

Kwon Jong-gun, director general of the North Korean Foreign Ministry's American affairs department, warned that the U.S. better mind its own business without meddling in inter-Korean issues if it wants to avoid "terrible" consequences.

In an interview with the North's official Korean Central News Agency, Kwon said inter-Korean relations are absolutely a matter between the two Koreas, and nobody has any right to meddle whatsoever.

The official said that if the U.S. does not want to face terrible things, it should shut its mouth and work on bringing its house in order first.

The remarks came after a U.S. State Department official said on Tuesday that the U.S. is "disappointed" in North Korea's recent actions.