(Bloomberg) -- The sister of North Korean leader Kim Jong Un said planned joint military exercises between South Korea and the U.S. will “cloud” inter-Korean relations, Yonhap News Agency reported.

North Korea will “closely watch” if South Korea goes ahead with the drills, report said, citing a statement from Kim Yo Jong via the Korean Central News Agency.

Kim Jong Un and South Korean President Moon Jae-in agreed in letters to restore relations, improving the prospects for a breakthrough in an extended stalemate in nuclear talks. The two countries released what appeared to be coordinated statements last week calling for reconciliation on the peninsula, with state media in Pyongyang saying they agreed “to make a big stride in recovering the mutual trust.”

South Korea and the U.S. tentatively agreed to hold exercises in the second week of August on a reduced scale, the DongA Ilbo newspaper reported last month, citing unidentified government officials. The drills were canceled in in the first half of 2020 because of the coronavirus pandemic and computer simulation drills were carried out in August 2020 and March 2021.

“I surely see the military drill, which takes place at an important turning point like this, will become an unpleasant prelude to seriously hurting the will of the leaders of the North and South seeking to take the step toward rebuilding trust again and further clouding the path lying ahead for inter-Korean relations,” Yonhap cited Kim Yo Jong as saying in the KCNA statement.

South Korea’s defense ministry said last week that the timing and scale of summer time military exercises with the U.S. haven’t been finalized, Yonhap reported July 29.

“Our government and military will closely watch whether South Korea will carry out their hostile war exercise once again or make a bold decision,” said Kim Yo Jong, who had been one of the most prominent faces in North Korea’s pressure campaign against the U.S. and South Korea. “Hope or despair? The decision is not upon us.”

The two Koreas reopened hotlines that had been silent since a flare-up a year ago, when Kim’s regime symbolically blew up a liaison office funded by Moon’s government. The U.S. has offered its support for the move by the two leaders to improve relations, saying it might help stalled nuclear talks.

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