Japanese Prime Minister Shinzo Abe has called North Korea's claim a 'serious threat' to Japan and a "grave challenge" to nuclear non-proliferation efforts.
According to CNN, Abe said that the test violates the United Nations Security Council (UNSC) resolution.
He also said that Japan along with the US, Russia, China and South Korea will take action against Pyongyang and discuss the matter at the UNSC.
The Hydrogen bomb test could take North Korea a step closer to developing nuclear warheads capable of striking the United States.
According to a statement, North Korea asserted that it would not abandon its nuclear weapons program as long as the US maintained what it called "its stance of aggression".
Following the test, a4.9 tremor was experienced and the Pentagon said that it was "looking into reports of a possible seismic event near North Korea's nuclear facilities."
South Korea's presidential office, meanwhile, has convened an emergency security meeting in Seoul. The country "strongly condemned" the test and warned Pyongyang that it would be made to "pay the price" for ignoring international opinion.