Tokyo, Sep 22 (IANS): The Japanese government on Friday said that it was prepared to face North Korea's threat to launch a hydrogen bomb into the Pacific Ocean.

Government spokesman Yoshihide Suga said at a press conference that the Japanese authorities were monitoring the situation closely, and described the North Korean regime's threat as unacceptable, reports Efe news.

"Japan will make every effort to protect the security of the Japanese people from cooperation with the US and South Korea," said Suga.

On Thursday, North Korean Foreign minister Ri Yong-ho said his country might test launch a hydrogen bomb in the Pacific as part of Kim Jong-Un's response to US President Donald Trump's UN speech, in which he called Kim "Rocket Man" and threatened to "totally destroy" Pyongyang

Ri said the test would be the most powerful ever in the Pacific.

Ri's comments came shortly after Kim in a direct statement called Trump "mentally deranged : and said that he would "pay dearly" for his "eccentric" speech.

Kim said that "now that Trump has denied the existence of and insulted me and my country in front of the eyes of the world and made the most ferocious declaration of war in history that he would destroy North Korea, we will consider with seriousness exercising a corresponding, highest level of hard-line countermeasure in history", which he claimed would be "beyond his expectation".