The South Korean navy Tuesday expressed "deep regret" over an accusation by the Democratic People's Republic of Korea (DPRK) that South Korean warships repeatedly intruded into the DPRK's territorial waters.

"We can't understand at all the North (DPRK)'s baseless claim which has been repeated this year. We also warn again that North Korea (DPRK) will bear responsibility for tension-heightening activities in the West Sea (Yellow Sea)," the South Korean Navy command said in a statement.

The statement also claimed that the South Korean vessels were on their regular patrol missions.

The statement comes one day after Pyongyang accused Seoul of sending a warship into its territorial waters off the west coast of the Korean Peninsula, thus, escalating tension along the disputed western sea border.

South Korea and the DPRK always had quarrels over the controversial inter-Korean sea border - the Northern Limit Line (NLL) - which was unilaterally drawn by the US-led United Nations Command after the end of the Korean War (1950-1953).

South Korea views the NLL as the de facto inter-Korean sea border, while the DPRK has not accepted it and claimed the sea border should be redrawn further south.

The navies of the two countries fought bloody gun battles in 1999 and 2002 that resulted in heavy casualties on both sides around the western part of the NLL.

Source: Xinhua