A North Korean military spokesperson slammed the recent military exercise carried out by South Korean, calling it a "reckless move" and "grave provocation", Pyongyang's state media reported on Friday.
"This is a grave provocation which can never be overlooked and this situation demands a necessary reaction from us, " the official Korean Central News Agency (KCNA) quoted the spokesperson as saying in its report.
According to the report, the South Korean military staged a joint military drill on Wednesday "in the hotspot waters in the West Sea of Korea" with the involvement of more than 20 fighters and storm boats, reports Xinhua news agency.
Such a reckless move does not help the efforts to defuse tension on the Korean Peninsula, the KCNA report said, adding that "everything is now going back to the starting point before the north - south summit meeting in 2018".
North Korean leader Kim Jong Un and South Korean President Moon Jae - in met in the border village of Panmunjom on April 27, 2018.
The two sides signed the Panmunjom Declaration, agreeing to complete denuclearization and begin a new era of peace.
The Kim - Moon meeting was the third inter - Korea summit and the first in 11 years.