The United Nations human rights investigator called on Monday (local time) for North Korean leader Kim Jong-Un and senior officials to be prosecuted for committing crimes against humanity.
Marzuki Darusman said North Korea is devoting huge resources to developing nuclear and other weapons of mass destruction while many of its citizens lack sufficient food.
He was addressing the UN Human Rights Council at a session boycotted by the North Korean delegation.
China, Pyongyang's ally, took a more conciliatory tone, saying human rights issues should not be politicised and calling for a comprehensive approach to dealing with North Korea.
Darusman, referring to his report issued last month, said: "I would like to reiterate my appeal to the international community to move forward to ensure accountability of the senior leadership of the Democratic People's Republic of Korea, including that of Mr Kim Jong-Un."
This could be via the International Criminal Court but failing a consensus among major powers, North Korea's leadership could be prosecuted in a third country, he said.
Political prison camps, torture, "slave-like labour" and religious persecution remain features of the state apparatus, two years after a landmark UN investigation into crimes against humanity, Darusman said.
"The denial of human rights to its citizens internally and this aggressive behaviour externally are basically two sides of the same coin," he said.
"The country is pouring a large amount of resources into developing weapons of mass destruction, while large parts of its population continue to suffer from food insecurity."
North Korea conducted its fourth nuclear test in January, followed by its launching of a long-range missile the following month.