ⓒKBS News

The powerful sister of North Korean leader Kim Jong-un in a statement Tuesday blasted South Korea and the United States for conducting a joint military exercise. 

Kim Yo-jong issued the criticism as Seoul and Washington kicked off preliminary training ahead of next week's main summertime military exercise. 

Kim said in the statement that South Korea and the U.S. started the drill that further escalates instability and that the North expresses "strong regret over the act of betrayal by South Korea."

Calling the exercise the expression of the U.S.' hostile policy against North Korea, Kim warned that the dangerous war rehearsal by South Korea and the U.S. in disregard of the North's repeated warnings will lead them to face a grave security threat.

She also said the Biden administration's North Korea policy of the so-called diplomatic engagement and dialogue without preconditions is nothing but hypocrisy and a disguise to hide its ulterior ambition of invasion.

Kim then added the North will continue to enhance its capabilities of national defense and preemptive attack to swiftly respond to any military action.

On the same day, South Korea’s Unification Ministry reported that its regular afternoon contact with North Korea via the liaison hotline at 5 p.m. did not go through,  adding it is closely watching the situation.

Senior diplomats of South Korea and the United States held phone talks on Tuesday evening to exchange assessments and opinions of the Korean Peninsula situation.

The ministry said the two sides agreed to continue coordinated diplomatic efforts for substantive progress in the denuclearization of and lasting peace on the peninsula.

They also agreed to continue consultation and exchanges of high-level officials.

The two sides are thought to have discussed the intent of the North's protest against the drills, the possibility of provocation and possible responses. 

Also on Tuesday, the United States reiterated that the joint military exercises with South Korea are purely defensive and that the U.S. holds no hostile intent toward North Korea.

U.S. State Department spokesperson Ned Price made the remarks on Tuesday during a news briefing when asked to comment on the North's criticism of the joint drills.

Price said he had no comment on the statement issued by Kim Yo-jong, but reiterated that the joint military drills are purely defensive in nature.

The spokesperson added that as the U.S. has long maintained, it harbors no hostile intent towards North Korea.

Despite Price’s remarks, North Korea continued the criticism on Wednesday.

Kim Yong-chol, head of the North's United Front Department handling inter-Korean affairs, warned that the North will make the South realize that it is approaching a "massive security crisis every minute" due to its wrong choice.

In a statement carried by the North's official Korean Central News Agency(KCNA), Kim said that South Korean authorities have rejected the opportunity to reverse the situation and engaged in a war rehearsal again on Tuesday.

Kim said Pyongyang should let Seoul pay the price for blowing away the opportunity to improve inter-Korean relations and to respond to the North's good will with hostile behavior.

He added that as long as South Korea and the U.S. have chosen confrontation with North Korea, the North has no other choice.