South Korea called on North Korea Friday to stop making unacceptable claims over the Gaesong Industrial Complex and hold talks to resolve pending problems including wage disputes.

It's "regrettable" that the North has not responded to the South's proposal that the two sides have talks on Friday, unification ministry spokesman Lim Byeong-cheol said at a press briefing.

"The government can never accept any unilateral system change (on the Gaesong complex) and it will cope resolutely with such a move in close cooperation with firms operating there," he said.

In February, Pyongyang announced its one-sided decision to raise the minimum wage for its workers in the joint venture from $70.35 to $74 starting in March. It also said it would collect 15 percent of their basic wage plus overtime payment as "social security." Currently, the South's firms pay 15 percent of the basic wage alone.

It would enable North Korea to earn $450,000 in additional revenue from the Gaesong district, according to the ministry.

Around 53,000 North Korean workers are employed by 124 South Korean firms, mostly small and medium-sized, in the zone created in 2004 as a result of the historic inter-Korean summit four years earlier.

On Thursday, the communist nation argued its wage hike decision is a legitimate measure under its sovereignty.

Speaking to Pyongyang's propaganda website, Uriminzokkiri, a spokesman for the country's Central Special Development Guidance Bureau said it is not a matter to be decided through consultations with the South's government. The bureau is in charge of operating the complex,

South Korean officials are apparently gearing up for a drawn-out dispute with the North, bearing various scenarios in mind.

"We do not rule out the possibility of the North withdrawing its workers from the facilities," Lim said. "We have advised companies there to follow the government-set guidelines (in any case)."

In April 2013, the North withdrew all of its workers and blocked the entry of South Koreans into the complex, suspending its operation for five months.

The ministry, meanwhile, dismissed the North's claim that its laborers in Gaesong are not being paid enough for their ability.

The North said their wage is still low for their heightened skills and productivity and in comparison with the wage level in special economic zones in other nations.

"The average monthly wage for the North's workers in the Gaesong Industrial Complex is $141.4," a ministry official said on background.

It's far higher than $74, the average wage per month in Bangladesh, and $120 in Cambodia, he pointed out.

"We were also told that the North's workers want to work in the Gaesong complex as its wage level and working conditions are better than those in other areas in their country," he said.

The government is willing to discuss the wage issue but it can't allow the North to make a unilateral decision, he added. (Yonhap)