An estimated 18 million North Koreans, or 70 percent of the population, suffer from acute food shortages and aid agencies provide "literally a lifeline" for 13 million of them, said UN Human Rights Commissioner Zeid Ra'ad Al Hussein.
"But sanctions may be adversely affecting this essential help," he told a special Security Council meeting on human rights in North Korea.
Sanctions that have tightened controls over international bank transfers "have caused a slowdown in UN ground operations, affecting the delivery of food rations, health kits and other humanitarian aid," he said.
The rights chief asked the council to conduct an assessment of the human rights impact of sanctions and urged them to take action to minimize consequences.
Over the past year, the council has adopted three rounds of sanctions aimed at choking off revenue to Pyongyang's military programs after Kim Jong-Un's regime carried out a sixth nuclear test and a series of advanced missile launches.
The council's sanctions committee on North Korea will meet later Monday to hear a briefing from a UN humanitarian official on the impact of recent punitive measures.
China fails to block rights meeting
The Security Council discussed the human rights crisis in North Korea despite objections from China, Pyongyang's ally.
China requested a procedural vote to block the meeting, but failed to garner enough support.
Ten countries voted to allow the meeting to go ahead, three opposed -- China, Russia and Bolivia -- while Egypt and Ethiopia abstained.
At least nine countries must back a contested agenda item for it to be discussed at the council and the veto does not apply.
Chinese Deputy Ambassador Wu Haitao said the council's discussion of rights abuses in North Korea was "counterproductive" at a time when tensions are running high on the Korean peninsula.
