The past 12 rounds of the on-and-off Cabinet-level negotiations produced little progress in easing decades-long military tensions.
At this week's talks, however, the North stepped back from its defiant stance and made some concessions, agreeing to hold high-level military talks to discuss ways to reduce tension.
North Koreans also accepted the South's demand to work for the success of multilateral negotiations to end the nuclear crisis.
It was a major departure from Pyongyang's long-held stance that it would not discuss the nuclear standoff and any other security issues with the South.
Analysts say the change in attitude by the North was largely motivated by a sense of crisis as international pressure is increasing over its nuclear weapons drive.
"North Korea appeared to think that time is not on its side," said Cheon Seong-whun, a researcher at the Korean Institute for National Unification, a government-run think tank.
"Pyongyang seems to feel increasingly cornered in the world community in the wake of revelations that a top Pakistani scientist had sold nuclear technology to North Korea," he said.
The progress is also attributable to Seoul's strategy to link the nuclear issue to economic aid for starving North Koreans, Cheon said.
At this week's four-day session, which ended Friday, the two Koreas agreed to hold high-level military talks in the near future to help ease military tensions and discuss ways to prevent accidental clashes.
The military dialogue, chaired by general-level officers, would deal with preventing clashes on their western sea border, where the two nations engaged in deadly gun battles during the past years.
The two Koreas held their first defense ministers' talks in September 2000. But they failed to open a second round of talks because North Korea had dismissed Seoul's repeated proposals for another meeting.
In recent years, South and North Korean Navy vessels have clashed at the disputed sea border of the Northern Limit Line, around which lucrative blue crab beds lie. Tensions have risen sharply in that zone for May-June and October-November crab seasons, when North Korean fishing boats often move into the contested waters in search of crab beds.
The NLL, a U.N.-imposed Korean maritime border established after the Korean War, has served as a neutral zone to avoid possible armed clashes. But the North says that it does not recognize the border, insisting on its own sea border far south of the NLL and including South Korean islands.
Seoul has aggressively sought high-level military dialogue with Pyongyang amid security concerns in the wake of Washington's decision to pull thousands of U.S. troops from the heavily fortified border with the North.
"The establishment of high-level channel between the two militaries is necessary to reduce tensions on the peninsula and ease security jitters in the South," said Kim Tae-hyun, a professor at Chung-Ang University in Seoul.
The North's 1.1 million-member People's Army, the world's fifth largest military force, has nearly twice the number of South Korean's military. Under North Korean leader Kim Jong Il's "army-first" policy, the military serves as the backbone of Kim's totalitarian rule. The country spends about 30 percent of its gross domestic product on the military.
South and North Korea also agreed to work together to make the upcoming six-way nuclear talks "fruitful" for a peaceful solution to the 15-month stalemate over Pyongyang's nuclear arms program.
The second round of the nuclear talks, involving the two Koreas, the U.S., China, Japan and Russia, is scheduled to begin Feb. 25 in Beijing. The first round, last August, ended without significant progress.
North Korea had refused to discuss the nuclear issue with South Koreans, saying the dispute was "a product of the U.S. hostile policy" toward Pyongyang.
South Korea Foreign Minister Ban Ki-moon said his government hopes the six-nation talks will generate an outcome in which North Korea "publicly declares" it will dismantle its nuclear programs.