Brazilian military planes have been ferrying food and other supplies to northern Brazil where weeks of heavy rain have caused widespread flooding.
Civil defence officials say at least 42 people have died and 274,000 people have had to leave their homes.
Floodwaters are subsiding in some areas but some rivers are reported to be still rising rapidly in Amazonas state.
The unusually heavy rains have hit regions used to downpours but also the arid north-east of Brazil.
Brazilian Air Force planes have been bringing in supplies of food, medicines, clothes and blankets.
Among the worst-hit areas is the state of Maranhao, where 65,000 people have had to leave their homes.
The town of Trizidela do Vale is said to be almost completely flooded.
Across the north and north-east, some one million people are said to have been affected by the floods.
In Amazonas state, several rivers are still rising, officials said, including the Rio Negro which flows past the state capital, Manaus.
The Rio Negro is just 74cm (29 inches) below a record high set in 1953, the state-run Agencia Brasil news agency reported.
President Luiz Inacio Lula da Silva said the floods and drought in two southern states signalled climate change.
"Brazil is feeling climate changes that are happening in the world, when there is severe drought in areas that don't have drought, when it rains too much in places where it doesn't rain," President Lula said in his weekly radio address on Monday.