South Korea has brushed aside North Korea's accusations that South Korean naval vessels have repeatedly violated the North's territorial waters.

North Korea claimed on Saturday that South Korean Navy vessels had intruded into its waters, the sixth such accusation in about three weeks.

The Joint Chiefs of Staff (JCS) said Sunday South Korean Navy vessels were only conducting ordinary patrol operations to guard the Northern Limit Line (NLL), the maritime demarcation border between the two Koreas by the U.N.

A JCS official said the North's statement may be related to its earlier declaration on Thursday that North Korea does have nuclear arms and will stay out of the six-party talks indefinitely.

The official said the statement appears aimed at escalating tensions on the Korean peninsula and to draw attention of the global community.