North Korean leader Kim Jong-un has heightened tensions on the Korean Peninsula by refusing to recognize the Northern Limit Line(NLL) and vowing to boost military preparedness by drawing a border in waters north of the islands of Yeonpyeong and Baengnyeong.

The North’s state-run Korean Central News Agency(KCNA) said Thursday that while overseeing the inspection test of a new surface-to-sea missile on Wednesday, Kim proposed ways to defend the North’s maritime border and crush any attempts to cross over by the navies of enemy forces.  

The report said Kim issued an order to boost military readiness in waters north of Yeonpyeong and Baengnyeong islands which often witness the intrusion of warships of enemy forces. 

The regime's leader said what is clear is that in the event enemy forces violate the maritime border recognized by the North, Pyongyang will regard the move as an infringement of the North’s sovereignty and an act of provocation. 

According to the unification ministry in Seoul, Thursday marked the first time the North used the term “maritime border.” 

In the past, Pyongyang has used the words “boundary” and “demarcation line” when referring to the maritime line dividing the two Koreas.