North Korean leader Kim Jong Un's sister and close aide, Kim Yo Jong, has lambasted joint military drills between the United States and the South that started Tuesday, saying they will "further imperil the situation on the Korean peninsula."

"Whatever the scale and mode, the joint military exercises are of an aggressive nature as they are a war rehearsal and preliminary nuclear war exercise," Kim Yo Jong said in a statement on the two countries' training exercise that began Tuesday and the annual summertime exercise starting next week, carried by the official Korean Central News Agency.

Kim Yo Jong. (Photo courtesy of Korea Media)(Kyodo)

"We will put more spur to further increasing the deterrent of absolute capacity to cope with the ever-growing military threat from" the United States, she added.

She said she released the statement "upon authorization," indicating Kim Jong Un may have instructed her to issue it.

July 27 marked the 68th anniversary of the signing of the armistice that suspended open hostilities in the 1950-1953 Korean War, in which the North was supported by China and the Soviet Union and the South was backed by U.S.-led U.N. forces.

On the same day, the two Koreas said Kim Jong Un and South Korean President Moon Jae In agreed to reconnect communications between the two nations, after exchanging several friendly letters since April.

But Kim Yo Jong said on Tuesday, "As long as U.S. forces stay in South Korea, the root cause for the periodic aggravation of the situation on the Korean peninsula will never vanish."


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