"The South Korean government is closely monitoring the situation and preparing for all contingencies, " said Kim Ho-nyun, a South Korean Unification Ministry spokesman.

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Although the president reiterated his firm stance on North Korea, South Korean Unification Minister Hyun In Taek met with North Korean unity leader Kim Yang Gon on Saturday.

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Chang Yong-seok, senior researcher at the Institute for Peace and Unification Studies at Seoul National University, suggested that the announcement was designed to remind the South Korean public that there is an ever-present danger from the North and to shore up support for the government's North Korean policy.

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