President Moon Jae-in said as the commander-in-chief, he feels responsibility over security lapses that allowed a North Korean boat to cross the border undetected last month.

At a luncheon with a group of elders from South Korea's military reserves on Friday, Moon recognized public concerns over a perceived lack of discipline and military preparedness.

The president added that the defense minister and the chairman of the Joint Chiefs of Staff(JCS) are taking stern measures in response to the incident.

Moon's remarks come as the opposition political parties are calling for a motion to dismiss Defense Minister Jeong Kyeong-doo.

It also remains to be seen whether Moon will replace Jeong during a Cabinet reshuffle expected to take place next month.