The security situation in the east of the Democratic Republic of Congo poses serious challenges for planned June elections, a UN report warns.
Fighting persists in the country's east despite a formal ceasefire
The report from UN Secretary General Kofi Annan says rebel groups from Rwanda are still operating in the area.
The UN's humanitarian chief Jan Egeland said on Thursday that about 1,000 people are dying every day in DR Congo.
A five-year civil war in the huge country left nearly three million people dead from hunger and disease.
The war is supposed to have ended in 2002 but fighting has persisted in the east, by soldiers who were once rebels backed by Rwanda.
In the report, which was to be presented to the UN Security Council on Thursday, Mr Annan says the security situation in the east remains "extremely volatile".
He says there are "serious challenges" to elections in June.
The UN also says it is worried about the logistics of holding elections in a country which is so large, yet lacks basic infrastructure.
Mr Egeland told reporters that credible estimates by the International Rescue Committee suggested about 1,000 people die every day in Congo - many from disease and malnutrition.
"It could be the biggest scandal of our generation in recent years, what happened really in the Great Lakes region, even after the genocide in Rwanda," he said.
He said while he was "increasingly satisfied" about the global response to the Asian tsunami disaster, he was "getting increasingly nervous for all of the forgotten and neglected emergencies".
Also in the report, Mr Annan said he was outraged by the sexual exploitation of women and girls by some UN staff in DR Congo.
Eight out of 72 allegations of sexual exploitation by UN troops in Bunia last year have been corroborated - most involving the soliciting of prostitutes, a violation of the UN peacekeepers' code of conduct, the report notes.
"I am afraid there is clear evidence that acts of gross misconduct have taken place. This is a shameful thing for the United Nations to have to say and I am outraged by it," Mr Annan says in the report.