Emergency meeting held in South Korea after Kim Jong Un's sister threatens military action

The South Korean military "is maintaining resolute military readiness to respond to all situations," the country's Defense Ministry said.

A visitor walks in front of a sign showing the distance to North Korea's Kaesong city and South Korea's capital, Seoul, near the wire fences at the Imjingak Pavilion in Paju, South Korea, on Sunday.Lee Jin-man / AP

South Korea convened an emergency security meeting Sunday after the sister of North Korea's leader threatened military action against South Korea in the latest escalation of tensions between the two neighbors.

Kim Yo Jong, a trusted aide to her brother, Supreme Leader Kim Jong Un, said she would leave the right to take the next step of retaliation against South Korea to North Korea's military in a statement carried Saturday by the state news agency, KCNA.

Kim, who has gained new prominence in North Korea's power structure, didn't specify what the next action could be or when exactly it would be taken, but she added: "I feel it is high time to surely break with the South Korean authorities. We will soon take the next action."

A spokesman for the Blue House, South Korea's presidential office, said Sunday that the national security council held an emergency video conference to review the situation and to discuss how best to respond.

The Unification Ministry, which handles relations with North Korea, said in a statement that the Koreas must do their best to abide by all inter-Korean agreements.

Kim Yo Jong, sister of North Korean leader Kim Jong Un, in Hanoi, Vietnam, on March 2, 2019.Jorge Silva / Reuters file

South Korea's Defense Ministry said separately that it was seriously assessing the situation and carefully monitoring North Korean movements. "South Korean military is maintaining resolute military readiness to respond to all situations," the ministry's statement said.

Kim's statement Saturday followed her announcement last week that North Korea was suspending all communication lines with South Korea, a move analysts believe could be an attempt to manufacture a crisis and force concessions from its neighbor.

North Korea said it was angered by defectors who have fled to the South and the routine flying of balloons over the border carrying propaganda leaflets.

South Korea responded by saying it would take legal action against two organizations that conduct such operations.

Kim Jin Ah, a North Korea expert at the Korea Institute for Defense Analyses, a government research center in Seoul, said North Korea is using propaganda leaflets as an excuse to break "the doldrum" in its negotiations with the U.S.

Nuclear talks with Washington remain deadlocked after Kim Jong Un's last summit with President Donald Trump in 2019 broke down without an agreement, and North Korea desperately needs relief in the face of harsh U.S.-led sanctions and the coronavirus pandemic.

"North Korea is using South Korea as a scapegoat and a stepping stone to build the context and the momentum for its engagement with the U.S. as the ultimate North Korean strategic goal is attracting the attention of the U.S., and President Trump in particular," Kim Jin Ah said.

Kim Jong Un's struggle to address economic woes has likely faced setbacks as the coronavirus pandemic forced North Korea to close its border with China, its biggest trading partner.

North Korea says it hasn't reported a single outbreak, but foreign experts have questioned that claim.

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Ramon Pacheco Pardo, a lecturer in international relations at King's College London, said it's reasonable from the North Korean perspective for the regime to try to divert attention from domestic conditions by raising tensions with South Korea.

"It makes sense for Kim Yo Jong to lead, or be seen as leading, these increasing tensions. This way she can show that she will be tough with South Korea if necessary," he said.

Pacheco Pardo said raising tensions is also a way for North Korea to try to force the South Korean government to put pressure on the Trump administration to allow sanctions exemptions, or even relief.

"It makes sense for North Korea to focus on raising tensions with South Korea, at least until we know the outcome of the U.S. November election and we can see what type of dynamic relations between Washington and Pyongyang will follow next year," he added.