South Korean President Park Geun-Hye today condemned North Korea's latest nuclear test as an act of "self-destruction" that will further deepen its isolation in the international community. The impoverished but nuclear-armed North staged its fifth nuclear test this morning, she said in a statement, describing it as a "grave challenge" to the international community. "With the nuclear test, Kim Jong-Un's regime will only earn more sanctions and isolation. and such provocation will further accelerate its path to self-destruction," she said, referring to the North's young ruler. The latest nuclear test - described as the North's most powerful to date by Seoul's military - proves Kim's "manic recklessness" and his obsession with building a nuclear arsenal despite global criticism, she added. In Tokyo, Japanese Prime Minister Shinzo Abe today called North Korea's latest nuclear test "absolutely unacceptable". "North Korea's carrying out of a nuclear test is absolutely unacceptable for Japan," Abe said in a statement, after Pyongyang conducted its fifth nuclear test, believed to be its most powerful to date. "North Korea's nuclear development is becoming a graver threat to Japan's safety and severely undermines the peace and safety of the region and the international community," Abe said. "Japan lodges a serious protest against North Korea and condemns it in the strongest language," he added.