Seoul, Feb 7 (IANS): South Korea's unification ministry on Sunday announced that it plans to further restrict the entry of its nationals into a jointly-run factory park in a border town of North Korea.

The number of South Koreans to be allowed to enter the Kaesong industrial complex will be reduced to 500 from the current limit of 650, the ministry said in a statement.

The reduction came after Pyongyang earlier in the day put an observation satellite into orbit aboard a long-range rocket, which Seoul considers a long-range ballistic missile, Xinhua news agency reported.

North Korea is banned under UN Security Council resolutions from a test of ballistic missile technology.

It was an additional reduction made by the ministry following Pyongyang's fourth nuclear test on Saturday.

The statement said the additional reduction will begin in consideration of safety of South Korean people working in the inter-Korean industrial zone.