North and South Korean delegates spent most of the day talking about talks, instead of actually holding them.

South Korean delegates headed to North Korea's Kaesong industrial zone early in the day, at the North's invitation, for a rare meeting amid the sharpest inter-Korean tensions in a decade.

But they spent most of the day trying to settle on basic protocols for the talks, and only began the real meeting after nine o'clock at night.  That conversation lasted a little less than 30 minutes.

South Korean Unification Ministry deputy spokeswoman Lee Jong-joo said the two sides spent many hours disagreeing over the venue and the agenda for the talks.

She said because those basic problems were not solved, the meeting was repeatedly delayed and never went into further discussion.

The Kaesong zone is an experiment in North-South economic cooperation, with South Korean factories hiring inexpensive North Korean manual labor.  North Korea has detained a South Korean executive who works there for more than three weeks, apparently for making sensitive political comments about the North's government.

Arranging the South Korean's return, and ensuring the safety of other South Koreans in Kaesong, were presumed to be the main agenda of the day's talks, but few details have been made available.

Experts said a likely subtext of the talks is South Korea's recently announced intention to join the Proliferation Security Initiative, or PSI.  That is a U.S.-led cooperative of more than 90 nations aimed at disrupting the transport of weapons of mass destruction.

North Korea has warned South Korea's full participation in PSI would be seen as a declaration of war.  The peninsula is already in a technical state of war, with only a 1953 armistice having halted fighting after North Korea's 1950 invasion of the South.