The situation in Haiti has been described as ‘critical’ after it was battered by Hurricane Matthew.
Christian Aid told Sky News it was likely to remain that way for 18 months.
Prospery Raymond from the charity said: “The south part of Haiti is really affected by Hurricane Matthew.”
Local officials said late on Friday afternoon that the number of dead had risen to 842.
The US Navy is sending the USS Mesa Verde to help with the relief effort.
Across the country, the International Red Cross said tens of thousands of people needed help as it launched a $6.9m appeal.
UNICEF said it needed $5m to provide initial aid to children.
Thousands of homes have been destroyed, while officials said that more than 60,000 people were in shelters.
Roads were flooded by sea and river water, while cell phone networks got cut off.
Most deaths are believed to have occurred in the southwest.
“Devastation is everywhere,” said Pilus Enor, mayor of the town of Camp Perrin on the peninsula’s south shore.
“Every house has lost its roof. All the plantations have been destroyed,” he said.
“This is the first time we see something like this.”
The southern city of Jeremie is said to have suffered “complete destruction”, while a bridge over the La Digue river in Petit Goave has been destroyed.
In Les Cayes – home to a major port – a cathedral roof has been blown off, and banana and mango crops been destroyed.
Source: Sky News