At least 1,941 people are known to have died in Haiti in Saturday's powerful earthquake - a rise of more than 500 on the previous figure, officials say.
Rescue workers have managed to pull 34 people alive from the rubble but many are still missing after the 7.2-magnitude quake.
The search for survivors has been hampered by heavy rains brought this week by Tropical Storm Grace.
Nearly 10,000 people have been injured and hospitals were left overwhelmed.
The UN says about 500,000 children now have limited or no access to shelter, safe water and food.
"Countless Haitian families who have lost everything due to the earthquake are now living literally with their feet in the water due to the flooding," said Bruno Maes, the UN Children's Fund (Unicef) representative in the country.