North Korea announced Saturday that 600 people are dead or missing in this month's flooding, twice the number estimated earlier by relief agencies.
The state run Korean Central News Agency cited figures from North Korea's Central Statistics Bureau. It says 100,000 people are homeless.
The United Nations is launching an international appeal for donations to help with immediate needs such as food, medical supplies, water and sanitation.
The U.N. appeal follows South Korea's announcement Friday it would help North Korea's effort to rebuild roads and thousands of homes destroyed in the floods.
Seoul already has delivered the first portion of its $40-million aid package to the North, and it pledges shipments of cement, iron bars, trucks, fuel and road materials will be complete by the end of this month.
The United Nations' deputy emergency relief coordinator, Margareta Wahlstrom, says floodwaters in North Korea are receding, and people who had evacuated are trying to return home.
The floods also wrecked much of the nation's grain crop.
Some information for this report was provided by AFP and AP.