The sister of North Korean leader Kim Jong Un has denounced planned joint exercises involving Japan, the US and South Korea as a "reckless show of strength."



Kim Yo Jong, vice department director of North Korea's ruling Workers' Party's Central Committee, released a statement on Sunday through the state-run Korean Central News Agency.



The US and South Korean militaries and Japan's Self-Defense Forces are scheduled to hold joint exercises, "Freedom Edge," aimed at responding to nuclear and missile threats from the North. The exercises will take place in the East China Sea and the airspace over the sea from Monday. South Korean media report that the US and the South will also stage a tabletop drill.



In the statement, Kim said North Korea would regard the exercises as "an unfiltered 'demonstration' of their anti-DPRK confrontational stand and 'succession' of confrontational policy." The DPRK stands for North Korea's official name -- the Democratic People's Republic of Korea.



She said, "The reckless show of strength" will "inevitably bring bad results," hinting that Pyongyang could take countermeasures.



Pak Jong Chon, vice chairman of the ruling party's Central Military Commission, also released a statement on Sunday.



Pak said, "The DPRK will make a very responsible choice under the present situation where all unreasonable actions of the enemy states against it are being systematically escalated."



The US and South Korean forces are bolstering their vigilance and surveillance activities toward North Korea ahead of the joint exercises.