SEOUL - South Korea's defence minister went to North Korea on Tuesday for a meeting of defence chiefs aimed at easing tensions along one of the world's most heavily armed borders.
The two Koreas agreed at a summit in October to set up a cooperation zone in disputed waters off their west coasts and start the first regular train service since the 1950-1953 Korean War, which ended in a ceasefire.
The measures require re-working security arrangements.
South Korean Defence Minister Kim Jang-soo will hold three days of talks with Kim Il-chol in Pyongyang. It will be the first meeting of defence chiefs in seven years.
One of the most contentious issues will be the maritime border called the Northern Limit Line (NLL).
It was set unilaterally by U.N.-led forces at the end of the Korean War and recognised since then by South Korea's military as the de facto border. Pyongyang declared the line invalid in 1999.
A few days after last month's summit, South Korean President Roh Moo-hyun said he was not sure if the NLL was a legal boundary.
This angered his critics, who said blurring the legality of the NLL compromises South Korea's territory and insults the soldiers who died defending it.
Dozens of sailors from both Koreas died in naval clashes in 1999 and 2002 over the disputed boundary.
The two Koreas have agreed to the regular train service from December. But the North's powerful military, fearful of increased contact with the outside, has blocked previous attempts to run trains at two crossings built by the South.
North Korea has a 1.2 million-strong military, most of whom are stationed near the border. The United States has about 28,000 soldiers in South Korea to support the country's 670,000 troops.
