Head of the United Nations Stabilisation Mission in Haiti, Sandra Honore, told the Security Council ahead of a vote on renewing the mission's mandate that damage from the hurricane was extensive, potentially affecting Haiti's stability.
"There can be no doubt: this is a humanitarian tragedy and an acute emergency situation with 1.4 million persons in need of immediate assistance," Honore said.
A presidential election scheduled for October 9 was postponed as well as partial senatorial votes and legislative reruns as Haiti struggles to recover.
"The impact of Hurricane Matthew on the political process and on the stability in the country can only serve to reconfirm the recommendation of the secretary-general for a six-month extension," said Honore.
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The council is to vote on Thursday on extending the MINUSTAH mission until April next year.
Council members however said plans for a drawdown of the force, which currently stands at 6,000, must not remain on hold for too long.
A strategic review is to be completed over the coming six months on a full pull-out of the mission, which could be replaced by a smaller UN presence.
UN Secretary-General Ban Ki-moon said Monday that a massive international response was needed to help Haiti as the United Nations launched a $120 million flash appeal for the next three months.
Hurricane Matthew killed at least 473 people in Haiti, according to a provisional count from authorities, with more feared dead as rescuers reach the hardest-hit areas.
The envoy said the health impact of the disaster cannot be overestimated, with water and sanitation infrastructure severely damaged, causing a high level of diseases including cholera.
Matthew crashed ashore on Haiti's southern coast on October 4 as a monster Category 4 storm, packing winds of 145 miles (230 kilometers) per hour.
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Floods in the US
Flooding in the aftermath of Hurricane Matthew has displaced several thousand people in North Carolina, and authorities were helping more evacuate on Tuesday as swollen rivers threatened a wide swath of the state.
Governor Pat McCrory warned of "extremely dangerous" conditions in the coming days in central and eastern North Carolina, where several rivers were at record or near-record levels after a storm blamed for 14 deaths in the state.
Matthew, the most powerful Atlantic storm since 2007, barreled through the US southeastern coast and killing more than 20 people in Florida, Georgia and the Carolinas.
An additional US death occurred on Monday night in Lumberton, North Carolina, where officials said a highway patrol officer fatally shot a man who became hostile and flashed a handgun during search-and-rescue efforts in fast-running floodwater.
Nearly 4,000 people have taken refuge in North Carolina shelters, including about 1,200 people in the hard-hit Lumberton area, where the Lumber River had crested at almost 4 feet (1.2 meters) above the prior record set in 2004 after Hurricane Frances.
A roadway is flooded by remnants of Hurricane Matthew on October 11, 2016 in Fair Bluff, North Carolina. (Getty) Source: Getty
Water blanketed the city of 21,000 people, leaving businesses flooded, homes with water up to their roof lines and drivers stranded after a stretch of Interstate-95 became impassable.
"We lost everything," said Sarah McCallum, 62, who was staying a shelter set up in an agricultural center after floodwaters drove her from her home of 20 years.
State officials are particularly concerned about victims like McCallum, who have no flood insurance because they do not live in areas typically prone to such inundation.
President Barack Obama on Monday signed a disaster declaration for North Carolina, which will make federal funding available to people in the hardest-hit areas.
Obama approved a similar declaration on Tuesday for South Carolina, where Matthew made landfall on Saturday. State officials are now urging residents to prepare for potential flooding from the Waccamaw and Little Pee Dee rivers.
About 532,000 homes and businesses remained without power in the US Southeast on Tuesday, down from the peak of around 2.2 million Sunday morning when the storm was still battering the Carolina coasts.
Worst flooding since Floyd
Matthew dumped more than a foot (30 cm) of rain in areas of North Carolina already soaked from heavy September rainfall.
It has triggered the worst flooding in the state since Hurricane Floyd in September 1999, the National Weather Service said.
That storm caused devastating floods in North Carolina, resulting in 35 deaths, 7,000 destroyed homes and more than $3 billion in damages in the state.
In Matthew's wake, officials are monitoring a number of overtopped or breaching dams in addition to the threat of inland river flooding, the governor's office said.
Concerns about a potential breach of the Woodlake Dam, which led to overnight evacuations in the central North Carolina town of Spring Lake, had eased by Tuesday afternoon after it was reinforced with 700 sandbags.
But there was preoccupation about Kinston, where significant flooding was already occurring from the Neuse River, which is expected to crest at about 27 feet (8 meters) on Saturday, just shy of the Floyd record, said National Weather Service meteorologist Lara Pagano.
Retired construction worker Wesley Turner, 71, said he fled his home near Kinston with his dogs on Friday after his power went out and the water quickly rose to about chest deep.
After several nights in a shelter, he did not know on Tuesday whether he had anything to return to.
"I can't get to my house because it is under water," Turner said.
