Officials say 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.
Nearly 10,000 people were injured, and many are still missing after the 7.2-magnitude tremor.
Rescue work had been hampered by heavy rains brought this week by Tropical Storm Grace to the Caribbean nation.
The United Nations said about 500,000 children now have limited or no access to shelter, safe water and food.
The UN Children’s Fund representative in the country, Bruno Maes said, “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.”
Tens of thousands of people left homeless by the quake had to decide whether to brave the storm under flimsy tarpaulins or risk returning into buildings damaged by the tremor and smaller aftershocks.
The south-west of Haiti appears to have suffered the worst of the damage from the quake, especially around the city of Les Cayes.
Some hospitals were left overwhelmed and in need of supplies, as medics struggled to treat the injured.
The earthquake compounds problems facing the impoverished nation, which is already reeling from a political crisis following the assassination of its president last month.
Prime Minister Ariel Henry, who is in power until fresh presidential election can be held, has declared a month-long state of emergency and urged the population to “show solidarity”.