South Korean soldiers clear barricade on Unification Bridge near the border village of Panmunjom, that has separates the two Koreas, in Paju, north of Seoul, South Korea, Monday, April 29, 2013. South Korea is preparing to pull out its last remaining nationals from a shuttered factory park in North Korea and empty out the complex for the first time since its 2004 opening. (AP Photo/Lee Jin-man)The Associated Press
Members of the media wait for South Koreans returning home from North Korea's Kaesong at the customs, immigration and quarantine office near the border village of Panmunjom, that separates the two Koreas, in Paju, north of Seoul, South Korea, Monday, April 29, 2013. South Korea is preparing to pull out its last remaining nationals from a shuttered factory park in North Korea and empty out the complex for the first time since its 2004 opening. (AP Photo/Lee Jin-man)The Associated Press
FILE - In this April 27, 2013 file photo, South Korean vehicles, overloaded with finished products, arrive back from North Korea's Kaesong industrial complex at the customs, immigration and quarantine office near the border village of Panmunjom in Paju, South Korea. Pyongyang has also taken an economic hit for its stance. Operations at the Kaesong factory park - a joint endeavor with South Korea just north of the Demilitarized Zone - have been suspended since early April, when the North barred South Korean factory managers and supply trucks from entering and withdrew all its 53,000 workers. (AP Photo/Ahn Young-joon, File)The Associated Press
PAJU, South Korea – North Korea delayed the departure of the last South Korean personnel from a joint industrial complex on Monday by not immediately giving them permission to return home across the two countries' border, South Korean officials said.
Officials from South Korea's Unification Ministry said North Korean officials had been meeting with the personnel for nearly four hours, but that the ministry still hoped that all 50 remaining South Koreans could be withdrawn on Monday.
Their departure would empty out the complex, located on the North Korean side of the border, for the first time since it opened in 2004 and possibly lead to the permanent closure of the last symbol of inter-Korean cooperation.
Two ministry officials refused to disclose what issues were being discussed at the meeting and said it was unclear when the South Koreans would be able to leave. They spoke on condition of anonymity because they weren't authorized to speak publicly on the matter.
Amid high tensions, North Korea suspended operations at Kaesong in early April, withdrawing all of its 53,000 workers and barring South Korean factory managers and trucks with supplies from entering the complex. It was the most significant action taken by North Korea to protest South Korean-U.S. military drills and U.N. sanctions imposed over a February nuclear test.
North Korea also issued a flurry of warlike rhetoric, including threats to launch nuclear strikes on the U.S., although it has recently shown some tentative signs of willingness to talk.
South Korea began withdrawing its remaining nationals from Kaesong on Saturday, citing a shortage of food and medicine for them, after North Korea rejected an offer to hold talks on the complex.
Kaesong, which combines South Korean knowhow and technology with cheap North Korean labor, is the last remaining cooperation project between the Koreas. The Korean Peninsula officially remains at war because the 1950-53 Korean War ended with an armistice, not a peace treaty.
Other joint programs, including tours to a scenic North Korean mountain, have been stalled in recent years because of confrontation between the rival Koreas.
Kim reported from Seoul.