Seoul, Apr 6 (IANS): South Korea's Unification Ministry said on Thursday it will take necessary steps if North Korea does not respond to Seoul's call to stop the unauthorized use of a now-shuttered joint industrial park in the North.

The Ministry's call came as Rodong Sinmun, the North's main newspaper, carried photos of South Korean buses running in Pyongyang on Wednesday that were used in the Kaesong Industrial Park to transport North Korean workers before the complex was closed down in 2016, reports Yonhap News Agency.

The Ministry said it attempted to notify North Korea of stopping the unauthorized use of the Kaesong complex earlier in the day, but the North has not responded as of now.

"The North's operation of factories in the complex without authorization constitutes a clear violation of South Korean businessmen's right to property and a related inter-Korean agreement," a Ministry official told reporters.

"The North should immediately stop its act. If the North does not reply to our call, the government will take necessary steps on the grounds that the North concedes its unauthorized use of the complex," he said, without elaborating.

South Korea shut down the industrial park in the North Korean border city of Kaesong in February 2016 in response to North Korea's nuclear and long-range missile tests.