North Korea has not responded for the second day to daily inter-Korean telephone calls that were restored two weeks ago. 

The Unification Ministry said Wednesday that its regular morning contact via the liaison hotline at 9 a.m. did not go through, while a military official confirmed that morning calls on its western and eastern lines were not answered either.

The two Koreas had kept in regular contact via the liaison hotline at 9 a.m. and 5 p.m. and the military lines at 9 a.m. and 4 p.m. every day since lines were restored on July 27.

The unanswered calls come after the sister of North Korean leader Kim Jong-un blasted preliminary South Korea-U.S. military training ahead of next week's main summertime military exercise. 

Earlier in the day, another powerful figure, 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 facing a "massive security crisis every minute" due to its "wrong choice."