The joint-Korean Kaesong Industrial Complex faces yet another problem as North Korea seeks to hike wages for its workers there.

The North on Tuesday refused to accept a letter from South Korea protesting against its revision of rules on workers' wages at the industrial park.

The North in early December unilaterally revised rules to scrap the five-percent limit on wage hikes.

Unification Ministry spokesman Lim Byeong-cheol said, "North Korea refused to accept our message. We will not allow any changes that do not result from inter-Korean discussions."

Lim added that the future of the Kaesong Industrial Complex cannot be guaranteed if the North insists on wage hikes without improving business conditions and labor productivity.

This year marks the 10th anniversary of the industrial complex.

North Korea's move is seen as an attempt to gain management control over the complex and boost its earnings.

Earlier complaints by the regime over snacks provided to workers and land use fees appear to have the same objective, a ministry official said.

The North Korean regime pockets most of the wages of workers in the guise of charging them various fees. Manufacturers have in many cases resorted to h anding out Choco Pie snacks to their staff since they are easily re-sellable in the black market.

Cho Bong-hyun of the IBK Research Institute said, "The North appears intent on taking over a lot of the responsibilities now being handled by the South. This will make South Korean manufacturers reluctant to remain there."

