The commission, which conducted a yearlong investigation, has found evidence of an array of such crimes, including "extermination," crimes against humanity against starving populations and a widespread campaign of abductions of individuals in South Korea and Japan.
Its report, due for release Monday, does not examine in detail individual responsibility for the alleged crimes but recommends steps toward accountability.
The three-member commission, led by a retired Australian judge Michael Kirby, was set up by the UN's top human rights body last March in the most serious international attempt yet to probe evidence of systematic and grave rights violations in the reclusive, authoritarian state, which is notorious for its political prisons camps, repression and famine that claimed hundreds of thousands of lives in the 1990s.
A spokesman for North Korea's UN Mission in New York, who refused to give his name, told AP: "We totally reject the unfounded findings of the Commission of Inquiry regarding crimes against humanity. We will never accept that."
The commission, which conducted public hearings with more than 80 victims and other witnesses in Seoul, Tokyo, London and Washington but was not refused access into North Korea itself, recommends that the UN Security Council refer its findings to the International Criminal Court in the Hague.