The government has expressed deep regret over North Korea's threat to scrap its accords with the South and nullify the western sea border between the two nations.

Unification Ministry spokesman Kim Ho-nyoun said Friday that inter-Korean agreements including the 1991 South-North Basic Agreement cannot be scrapped unilaterally.

The spokesman also said the sea border in the Yellow Sea must be respected by both South and North Korea until an official agreement is made on a new border in accordance with the South-North Basic Agreement.

He also said that the current Northern Limit Line (NLL) has been a de facto maritime demarcation line for the past 50 years.

Kim also called on the North to agree to dialogue, urging Pyongyang to realize that heightened tension between the two sides will not contribute to inter-Korean relations or peace in Northeast Asia.