South Korea is scrutinizing North Korea's unilateral decision to amend a number of wage-related clauses at the jointly operated Kaesong Industrial Complex, an official said Tuesday. 

As soon as a review of the North's demands are finished, the government will take appropriate steps, the unification ministry official told reporters.

"We are in the process of reviewing and analyzing the contents revised by the North," he said on background.

The South and the North have an agreement over 49 items in place on the working conditions for around 53,000 North Korean workers in the zone.

Without prior consultations with the South, the North announced its decision to revise 13 of them, which include scrapping a 5-percent cap on the annual minimum wage increase rates, easing qualifications for severance pay and strengthening the authority of the North's agency in charge of running the complex, according to the official.

North Korean workers' wages have jumped 5 percent every year since 2007. North Korean workers are currently paid US$70.35 each month. If various allowances and incentives are counted, wages reach $130, reportedly about 50 percent higher than the average income of workers in North Korea.

More than 120 South Korean firms, mostly small and medium enterprises, run operations at the Kaesong facilities located just north of the inter-Korean border.

The complex, created in 2004, is designed to draw synergy effects from the North's cheap labor and the South's capital and technology. (Yonhap)