North Korean leader Kim Jong Un's sister, Kim Yo Jong, released a statement Saturday predicting the destruction of the joint liaison office set up in the country's border city of Kaesong as the next stage of retaliation over anti-Pyongyang leafleters, according to official media.

"I feel it is high time to surely break with the south Korean authorities," she said in the statement carried by the Korean Central News Agency. "We will soon take a next action."

"By exercising my power authorized by the Supreme Leader, our Party and the state, I gave an instruction to the arms of the department in charge of the affairs with enemy to decisively carry out the next action," the statement said.

"Before long, a tragic scene of the useless north-south joint liaison office completely collapsed would be seen," she added.

The statement comes a little over a week after she warned that Pyongyang may scrap a military pact with the South and shut down Kaesong as well as the liaison office located there if Seoul fails to prevent defectors from scattering leaflets critical of the North.

On Tuesday, KCNA reported that North Korea decided to cut off all lines of communication with South Korea authorities in protest at Seoul's inability to stop the groups' leaflet-sending activities.

Since that day, routine calls to North Korea via the liaison office and military communication lines have gone unanswered, according to the South Korean government.

Following Kim Yo Jong's threats, South Korea's Unification Ministry on Wednesday said it would charge two activist groups known for sending balloons carrying leaflets across the border.

It accused the groups, which are led by North Korean defectors, of violating an inter-Korean cooperation law.

At their summit in April 2018, Kim Jong Un and South Korean President Moon Jae In signed the Panmunjeom Declaration, in which the two Koreas pledged to set up a joint liaison office and cease all hostile acts including flying leaflets to eliminate the risk of war.

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