Cyclone Idai claimed more than 200 lives in Mozambique and the death toll could grow exponentially, President Filipe Nyusi said Tuesday.

"We came here with 84 (confirmed deaths), but afterwards on the ground we were seeing that we are already at more than 200. And not only that, but there are also 350,000 citizens in risk situations," he said following an emergency Cabinet meeting in Beira, Mozambique's fourth-largest city and a major port.

Mozambican authorities estimate that as many as 600,000 people have been affected by the storm.

Idai slammed into Beira five days ago, all but destroying the city of more than 500,000 people before moving inland over Malawi and Zimbabwe.

Thousands of Mozambicans in districts near Beira, including Buzi, Chibabava, Muanza, Mossurize and Sussundenga, remained perched atop trees and on the roofs of the few buildings left standing amid river flooding.

The United Nations Office for the Coordination of Humanitarian Affairs said that the next 72 hours will be critical for Mozambique, given that heavy rains continue to fall over the affected areas.

More than 100,000 people are in danger as a result of Idai, Save the Children said Tuesday.

"The scale of this disaster is growing by the minute and Save the Children has grave concerns about children and their families still at risk," the leader of the organization's response in Mozambique, Machiel Pouw, said via Twitter.

Meanwhile, the European commissioner for humanitarian aid and crisis management, Christos Stylianides, announced emergency aid of 3.5 million euros ($3.9 million) for Mozambique, Malawi and Zimbabwe.

The cyclone is blamed for 82 deaths in Zimbabwe and another 56 in Malawi.

The regional director for the UN World Food Program in Southern Africa, Lola Castro, told EFE by telephone that her organization was focusing its efforts on saving lives, describing the cyclone as an "unprecedented disaster."

Castro added that high-energy biscuits were being airlifted and distributed to people in Beira.

The United Nations and its humanitarian partners in Mozambique have appealed for $40.8 million to provide urgent aid to the stricken African country.