Warning termed 'totally unacceptable' by Japan even as Kim Jong-un vows to make 'mentally deranged' Trump pay dearly.

Warning termed 'totally unacceptable' by Japan even as Kim Jong-un vows to make 'mentally deranged' Trump pay dearly.

North Korea says it may test a hydrogen bomb over the Pacific Ocean after US PresidentDonald Trump threatened to destroy the country, whose leader responded by promising to make a "mentally deranged" Trump pay dearly for his threats.

Speaking in New York City on Friday, Ri Yong-ho, North Korea's foreign minister, said his country could consider a hydrogen bomb test on an unprecedented scale on the Pacific Ocean, South Korea's Yonhap news agency reported.