SEOUL, April 26 (Reuters) - North Korea rejected on Friday a South Korean proposal for talks aimed at restarting a joint factory zone saying the South has acted in an "unpardonable" manner to jeopardize a "precious" legacy of the rivals' bid to seek peace.
The North's National Defence Commission, its supreme leadership body, repeated that what it saw as the reckless behavior of the South had thrown into question the safety of the zone's operation and had forced it to stop access there.
The Kaesong industrial zone is just inside North Korea.
"If the South's puppet regime turns a blind eye to reality and continues to pursue a worsening of the situation, we will be forced to take a final and decisive important measure," a spokesman for the commission was quoted as saying.
The Kaesong industrial zone opened in 2004 as part of a so-called sunshine policy of engagement and optimism between the two Koreas, still technically at war after their 1950-53 war conflict ended in a truce, not a treaty.
About 53,000 North Koreans worked at the complex where 123 South Korean companies have set up small- and medium-sized factories.
The zone was a lucrative source of cash for the impoverished North, providing it with almost $90 million a year. South Korean manufacturers have been paying about $130 a month to North Korea for each of the workers they employed.
The North withdrew its workers this month amid spiralling tension between the two Koreas. North Korea said the United States and the South were to blame because of what it sees as threatening U.S. and South Korean military exercises.
On Thursday, South Korea proposed formal talks between the governments as the 170 or so South Korean workers who remain there are believed to be running out of food and other supplies. It had demanded an answer from the North by Friday.
North Korea has prevented South Korean workers and supplies from getting in to the zone since April 3.
The number of South Koreans in the zone has dwindled from the 700 or so normally needed to keep the factories running to about 170, seen as the minimum number needed to safeguard assets at the 1 trillion won ($894.73 million) park.
North Korea stepped up defiance of U.N. Security Council resolutions in December when it launched a rocket that it said had put a scientific satellite into orbit. Critics said the launch was aimed at developing technology to deliver a nuclear warhead mounted on a long-range missile.
The North followed that in February with its third test of a nuclear weapon. That brought new U.N. sanctions which in turn led to a dramatic intensification of North Korea's threats of nuclear strikes against South Korea and the United States. (Reporting by Jack Kim; Editing by Robert Birsel)