The South Korean Navy has refuted North Korea's claims that South Korean military vessels are making daily intrusions into its territorial waters.

The Navy spokesman said in a statement Wednesday that South Korean vessels had never violated the Northern Limit Line, a de facto maritime border in the Yellow Sea separating the two Koreas.

The statement blamed the communist state for raising military tensions, calling the North's claims untrue and incomprehensible.

The statement also characterized as a military provocation the North's warning of a possible inter-Korean maritime clash, pointing out that it comes amid active exchange and cooperation between the two Koreas.

Earlier in the day, the North's Korean Central News Agency quoted a report by Pyongyang's naval command as saying that Southern vessels were illegally entering the North's territorial waters five or six times a day and warning of another possible naval clash.

In June of 1999 and 2002, the two Koreas engaged in naval skirmishes along the maritime border in the Yellow Sea during the crab season.