Fighting between army chief Abdel Fattah al-Burhan and his former deputy, Mohamed Hamdan Daglo, has since April killed tens of thousands and led to acute food shortages and a looming famine.
"By all measures -- the sheer scale of humanitarian needs, the numbers of people displaced and facing hunger -- Sudan is one of the worst humanitarian disasters in recent memory," Edem Wosornu, director of operations at the UN Office for the Coordination for Humanitarian Affairs (UNOCHA), said.
"A humanitarian travesty is playing out in Sudan under a veil of international inattention and inaction," Wosornu told the Security Council Wednesday on behalf of UNOCHA head Martin Griffiths.
"Simply put, we are failing the people of Sudan," she added, describing the population's "desperation."
According to the UN, the conflict has seen more than 8 million people displaced.
In total, more than 18 million Sudanese are facing acute food insecurity -- a record during harvest season, and 10 million more than at this time last year -- while 730,000 Sudanese children are thought to suffer from severe malnutrition.
Griffiths warned the Security Council last week in a letter seen by AFP that "almost five million people could slip into catastrophic food insecurity in some parts of the country in the coming months."
UN World Food Programme's deputy executive director Carl Skau said Wednesday, "If we are going to prevent Sudan from becoming the world's largest hunger crisis, coordinated efforts and joined up diplomacy is urgent and critical."
He cautioned there is a "high risk" the country could see famine levels of hunger when the agricultural lean season begins in May.
Malnutrition is "already claiming children's lives," Wosornu said, adding that humanitarian experts estimate some 222,000 children could die of the condition in the coming weeks and months.
Additionally, she said, children weakened from hunger are at a higher risk of dying from other preventable causes, as more than 70 percent of the country's health infrastructure has collapsed.