“North Korea must live up to its promises it made in the past and achieve denuclearization on the Korean Peninsula,” Mr. Cho said, according to Yonhap.
Japan’s Cabinet Secretary Yoshihide Suga said the move would need to be dealt with in a serious manner, also noting that it was a breach of previous North Korean commitments.
U.N. Secretary-General Ban Ki-moon, who is South Korean said he was “deeply troubled” by the news, CNN reported.
“The current crisis has already gone too far,” Mr. Ban said in a statement from Andorra. “Nuclear threats are not a game. Aggressive rhetoric and military posturing only result in counter-actions, and fuel fear and instability.
“Things must begin to calm down, as this situation, made worse by the lack of communication, could lead down a path that nobody should want to follow.”
In Beijing, the spokesman for the Foreign Ministry, Hong Lei, said that China, the North’s only major-nation ally and largest trading partner, was “regretful” about the news.
“We have noticed the statement made by the DPRK and feel regretful about it,” Mr. Hong told a daily briefing for reporters, according to the New York Times. China urged “all parties to remain calm and restrained,” he said.