North Korean leader's powerful sister Kim Yo-jong is seated across from President Moon Jae-in during a lunch at Cheong Wa Dae on Feb. 11, 2018. Yonhap

By Do Je-hae

North Korea threatened to scrap the 2018 inter-Korean agreement Thursday if Seoul did not act quickly to stop anti-Pyongyang leaflets being sent over the two countries' border by defectors' groups based in South Korea.

North Korean leader Kim Jong-un's sister Kim Yo-jong said in a statement published by the Korean Central News Agency that the North could consider not only scrapping the pact, but also terminating exchange projects with the South if the latter did not stop the "hostile activities."

"If the South Korean authorities fail to come up with proper measures, they will have to be fully ready to face the consequences, whether it be the abolition of the Mount Geumgang tour program, a complete removal of the Gaeseong Industrial Complex, a closure of the inter-Korean liaison office or the scrapping of the North-South military agreement," she said in the statement.

Kim Yo-jong, who serves as first vice department director of the Central Committee of the Workers' Party of Korea, claimed that the floating of balloons containing anti-North Korea leaflets over the border by civic groups who promote North Korean defectors' rights were in violation of the Panmunjeom Declaration signed during the first summit between President Moon Jae-in and Kim Jong-un on April 27, 2018.

S. Korea to legislate ban on anti-Pyongyang leaflet campaign after NK threats