|Tensions between North and South Korea have deteriorated after the sinking of the Cheonan warship in March [AFP]
North and South Korea have ended their first military talks in two years without making progress on efforts to ease cross border tensions, officials from the South say.
Seoul's defence ministry said on Thursday that officers from the two sides met at the border truce village of Panmunjom after the North accepted the South's revised date for the meeting.
The meeting was aimed at easing tensions heightened by the sinking of a South Korean frigrate near the nations' disputed sea border in March, but the talks broke down after about two hours over the fate of the Cheonan.
South Korean officers "strongly urged North Korea to admit to, apologise for and punish those responsible for the attack on the Cheonan warship", the defence ministry said in a statement.
It also demanded the North "immediately stop its military threats and aggressive behaviour at sea borders".
But the North said it could not accept the findings of an international investigation, which blamed the sinking and the death of 46 sailors on a North Korean torpedo.
It reiterated its demand that North Korean investigators be allowed to examine the results.
North Korea also called on the South at Thursday's meeting to stop activists from sending propaganda leaflets across the border, and complained that the South's warships have been crossing the disputed Yellow Sea border.
However, the South said that "responsible actions" by the North on the Cheonan incident are the key to solving the differences between the nations, the ministry statement said.
The two sides did not set a date for a second round of talks, a ministry official told South Korea's Yonhap news agency.
Don Kirk, the Korea correspondent for the Christian Science Monitor, said the failure to reach agreement at the talks came at no surprise.
"How are they going to make progress? North Korea is certainly not going to apologise or even acknowledge the sinking of the Cheonan," he told Al Jazeera from Seoul.
"And there's not going to be a lot of change in the limit line in the Yellow Sea, which was the whole issue that triggered the Cheonan incident. So I'm not surprised there's no progress.
"On the other hand, the fact that they met at all is progress in itself. They haven't met in two years and it's quite surprising that they should meet at all."
The poorly marked western sea border, drawn by the UN at the end of the 1950-53 Korean War, is a constant source of tension between the two Koreas.
Seoul has repeatedly rejected the North's long-standing demands that the sea border be changed. The navies of the two Koreas engaged in three bloody skirmishes near the area in 1999, 2002 and 2009.
Military tensions have been high since the Cheonan's sinking. South Korea and the US say the vessel was sunk by a North Korean torpedo, a claim Pyongyang denies.
Seoul and Washington responded to the sinking by staging a series of joint military exercises off the peninsula, and by squeezing the North's economy with tougher sanctions.
The talks on Thursday came as South Korea and the US hold another set of naval drills in the Yellow Sea off the west coast of the Korean peninsula, near where the South Korean vessel sank.
The exercises are the second in a series of joint manoeuvres focusing on anti-submarine warfare tactics, techniques, and procedures, according to the South Korean defence ministry.