A failing public distribution system, corruption and the diversion of Pyongyang's limited resources to its military have made life particularly difficult for those outside the showcase capital of Pyongyang, Zeid said.

"Every effort must be made to ensure the government of the DPRK makes urgent changes to the country's laws and policies to enable greater freedom and enable access to fundamental services and goods," he said.

Zeid also noted that the recent sanctions have caused difficulty for aid agencies on the ground, specifically the stringent banking restrictions, and asked the Security Council investigate the human rights impact of sanctions.

With the arrival of blistering weather, concerns are mounting over the plight of ordinary North Koreans. The capital of Pyongyang was forecast to hit a high of 16 degrees Fahrenheit (-9 degrees Celsius) with an low of 1 degree (-17 degrees Celsius) Tuesday.

Military money

The sanctions passed this year are aimed at stopping North Korea's weapons programs by limiting items it can purchase on the international market and squeezing its ability to bring in revenue internationally, in the hopes that it will eventually trade nuclear weapons for sanctions relief.

"Every ounce of revenue North Korea receives they put to their nuclear program. So the fact that sanctions have completely squeezed them, that's less money they can put towards that nuclear program," she said.

But North Korea says its nuclear program is non-negotiable, something that US President Donald Trump appeared to acknowledge at a rally Friday.

"I don't know that sanctions are going to work with him (Kim Jong Un). We've got to give it a shot," he said.

Analysts say the country's military and nuclear programs are likely the last things it would cut, as the country operates under a military-first policy known as "songun."

North Korea spends nearly 25% of its GDP on its military, according to US State Department figures (last year, the US spent 3.6% of its GDP on defense). The country's armed forces reportedly have more than a million people on active duty, with millions more in reserve.

The Kim regime justifies these large expenditures due to the narrative of an impending attack by the United States and its allies. The nuclear weapons and missiles programs, which have demonstrated considerable progress this year, are sold as the ultimate insurance policy to deter a potential US invasion.

Food and fuel

Stories and reports issued at separate UN events Monday painted a grim picture of life inside inside the hermit state.

Zeid noted that North Korea is putting up barriers on its border and increasing checkpoints throughout the country -- measures intended to deter would-be defectors from fleeing.

Zeid said his office received reports of defectors carrying poison. In one incident, a family of five reportedly committed suicide after being caught, likely due to fears as to what would happen on their return to North Korea.

Ji Hyeon-a, a North Korean who was forcibly repatriated three times before successfully defecting, spoke about the horrors of her experience at a prison camp in North Korea, during a side-event at the UN Monday.

"Everyone was subject to harsh labor and meals were so lacking that we ate raw locust, discarded cabbage leaves and skinned frogs and rats," she said. "People died withered and dehydrated from continuous diarrhea ... the dead bodies end up becoming food for the dogs."