North Korea has yet to resume operation of an inter-Korean military communication line as of Monday morning after South Korea requested to reopen the hotline to discuss a joint probe into North Korea's killing of a South Korean fisheries official. 

A South Korean government source said the North continues to have the hotline turned off.

The two sides used to hold regular phone calls using their eastern and western military hotlines twice each day at 9 a.m. and 4 p.m. but Pyongyang has been unresponsive since June 9 after taking issue with anti-North leaflet campaigns conducted by defectors groups in South Korea.

Meanwhile Seoul's Joint Chiefs of Staff said North Korea has shown no unusual movements near the Northern Limit Line, which serves as a de facto maritime border on the West Sea.

The North earlier warned the South not to intrude into its waters as it searches for the remains of the slain official.

Seoul's Defense Ministry's deputy spokesperson Moon Hong-sik told a regular briefing that South Korea's stance remains unchanged in that the NLL is the de facto maritime border that must be adhered to and respected.

He added that search operations for the body of the fisheries official are ongoing.  

On Sunday, South Korea urged the North to restore the military hotline so the two sides can discuss conducting a joint investigation into the shooting death.