Mozambique's death toll from flooding in the wake of Cyclone Idai more than doubled as relief workers struggled to deal with the devastation wrought by the storm.

The number of dead has increased to 202, Mozambique's cabinet said, as it declared a national emergency. President Filipe Nyusi said the toll could exceed 1,000. In neighboring Zimbabwe, at least 98 people have died and that figure could reach 300, according to its government.

The storm caused flooding over an area of 394 square kilometers (152 square miles), according to European Union satellite imagery. Already more than 1.5 million people have been affected in the region, the United Nations said.