(CNN)U.N. Secretary-General Ban Ki-moon said his planned visit Wednesday to a joint industrial complex has been canceled by North Korean authorities.
U.N. chief: North Korea cancels visit
In a speech in Seoul, the secretary-general said there was no explanation given by the North Koreans for the last-minute change.
"This decision by Pyongyang is deeply regrettable. However, I, as the Secretary-General of the United Nations, will not spare any efforts to encourage the DPRK (Democratic People's Republic of Korea, or North Korea) to work with the international community for peace and stability on the Korean peninsula and beyond," Ban said, according to a U.N. statement.
The Kaesong Industrial Complex lies north of the Demilitarized Zone (DMZ) that divides the two Koreas. More than 100 South Korean factory owners employ about 50,000 North Korean laborers to manufacture products such as clothing and shoes.
The complex was established more than a decade ago at a time when a previous government in South Korea was pursuing a "sunshine policy" of friendship with its reclusive northern rival.
Its creation allowed South Korean companies to benefit from the low cost of North Korean labor. Meanwhile, North Korea gained a valuable stream of hard currency revenue by appropriating an undisclosed amount of salary from its citizens working in Kaesong.