High-level military talks between North and South Korea have broken down after the two sides failed to make progress on a long-running border dispute.
The talks began with optimism, but broke up without agreement
The North Korean side walked out of the talks after concluding that they were "fruitless", their chief delegate said.
North Korea wants the sea border to the west of the Korean Peninsula to be redrawn further south.
The area lies in rich fishing grounds and has been the scene of bloody naval clashes in the past.
Military discussions between the two Koreas have faltered in the past because of the ongoing dispute.
The three-day talks, in the truce village of Panmunjom, are the highest-level military dialogue between the two Koreas, who have not signed a peace treaty since the 1950-53 Korean War.
Issues such as preventing naval clashes and providing security for joint economic projects were also on the agenda, but analysts had expected that the sea border row would dominate proceedings.
Pyongyang does not recognise the border, known as the Northern Limit Line, which was drawn up by the UN at the end of the Korean War.
It is adamant that the border must be moved and accuses South Korean ships of repeatedly violating its territorial waters.
The area has been a trigger for clashes in the past. Six South Korean sailors were killed in one incident in June 2002.
"We've come to a conclusion that we don't need these fruitless talks any more," North Korean delegation leader Lt-Gen Kim Yong-chol said as the talks broke down.
The South Korean delegation head, Maj-Gen Jung Seung-jo, said it was "highly regrettable that we have to wrap up the three days of talks with no concrete results".
"Your side continued making this demand even though your side knows very well that our side cannot accept it," he said of the border issue.
The talks came amid a wider improvement in North Korea's ties with the outside world.
Last week it finally shut down its Yongbyon nuclear reactor after months of negotiations.
The closure was part of an international disarmament deal under which North Korea is to receive energy aid and political incentives in return for ending its nuclear programme.