The U.N. special rapporteur on North Korea's human rights situation called on the U.N. Human Rights Council to officially notify North Korean leader Kim Jong-un that he may be investigated and held accountable for crimes against humanity.

Marzuki Darusman made the remark in a report to the council disclosed Monday, saying the human rights situation in the North has not improved and the crimes against humanity documented by a U.N. Commission of Inquiry appear to be ongoing.

The special rapporteur "calls upon the Human Rights Council to arrange to have an official communication ... addressed to the Supreme Leader of the Democratic People's Republic of Korea to advise him and other senior leaders that they may be investigated," he said in the report.

The North's leader and other officials should also be notified that if found to be responsible, they may be "held accountable for crimes against humanity committed under their leadership," the rapporteur said in the report available on the council's website.

According to the principle of command and superior responsibility under international criminal law, military commander and civilian superiors are criminally responsible for failing to prevent or repress crimes against humanity committed by people under their effective authority and control, Darusman said.

"Consequently, the criminal responsibility of the uppermost leadership of the Democratic People's Republic of Korea, including the Supreme Leader, for crimes against humanity must be considered, for ordering or instigating such crimes, even if lower-ranking officials carried out the crimes," he said.

He also called for extending the mandate of the special rapporteur, "given that the situation of human rights in the Democratic People's Republic of Korea has hardly improved."

North Korea has long been labeled one of the worst human rights violators in the world. The communist regime does not tolerate dissent, holds hundreds of thousands of people in political prison camps and keeps tight control over outside information.

But Pyongyang has rejected accusations of human rights abuses as evidence of the U.S.' hostile policy toward it.

The North's human rights violations have drawn greater international attention since the U.N. Commission of Inquiry issued a report in early 2014, calling for referring the North to the International Criminal Court for "crimes against humanity."

That has led the U.N. General Assembly to adopt a resolution calling for the North's referral to the ICC for two years in a row: in 2014 and 2015. (Yonhap)