Kim Yo-jong, North Korean leader Kim Jong-un's sister and currently vice department director of the ruling Workers' Party's Central Committee, is pictured as she visits the Ho Chi Minh mausoleum in Hanoi, on Mar. 2, 2019. (Yonhap)

Kim Yo-jong, the influential sister of North Korean leader Kim Jong-un, on Thursday mocked South Korea's Hyunmoo-5 missile, first showcased in a recent military parade in Seoul, as a "uselessly huge weapon."

Kim Yo-jong made the remark in a statement carried by the North's Korean Central News Agency, just two days after South Korea unveiled the missile, known to be able to carry an eight-ton warhead, in a military parade marking Armed Forces Day.

In a ceremony marking the anniversary, President Yoon Suk Yeol said North Korea will face the end of its regime if it attempts to use nuclear weapons, warning of a "resolute and overwhelming" response from the South Korea-U.S. alliance.

"If they had a certain amount of common sense, who could speak about the 'end of regime' while boasting a uselessly huge weapon," Kim said in the statement.

Kim also condemned the appearance of a U.S. B-1B heavy bomber during the Armed Forces Day ceremony, calling it a "scene that is only possible in colonialized South Korea."

The North Korean leader's sister went on to criticize the South Korean military's establishment of its Strategic Command, saying it is not fitting for a "pack that does not possess one single strategic weapon."

The new military command officially launched earlier this week to serve as an overarching organ for the South's key weapons systems to deter evolving North Korean nuclear and missile threats. (Yonhap)