The United Nations is making an emergency appeal for 282 million dollars (£214 million) for the next three months to help Mozambique start recovering from the devastation of Cyclone Idai.

The funding will be used to provide water, sanitation, education and restoring the livelihoods of the hundreds of thousands of displaced people, UN humanitarian chief Mark Lowcock said.

He said separate appeals will be made shortly for Zimbabwe and Malawi, also hard-hit by the cyclone.

Mr Lowcock said funds are starting to come through, including £22 million from the UK, but are far outstripped by the needs.

Unicef head Henrietta Fore visited Mozambique’s ravaged port city of Beira and said “it’s a race against time” to help the displaced and prevent disease.

Authorities in Mozambique say that with a key road open to the badly damaged city of Beira, conditions on the ground improving and more international help arriving, vital aid to those hit by Cyclone Idai should flow more freely.

Idai’s death toll has risen above 750 in the three southern African countries hit 10 days ago by the storm, as workers rush to restore electricity, water and try to prevent outbreak of cholera.

In Mozambique the number of dead has risen to 446 while there are 259 dead in Zimbabwe and at least 56 in Malawi for a three-nation total of 761.

The death toll is “very preliminary”, said Mozambique’s environment minister Celso Correia, who said it is expected to rise.

The US military will join international aid groups assisting in providing food and medical care to those affected by the massive cyclone, one of the worst natural disasters in southern Africa in recent history.

Some 228,000 displaced people are in camps across the vast flooded area of Mozambique, said Mr Correia, who is the government’s disaster co-ordinator. It is still too early to give a number of missing, he said.

Diarrhoea is reported in camps but he says it is too early to say whether it is cholera. He has said it is almost certain the disease will emerge.

Aid teams are going to high points on islands created by Idai and finding “a lot of people”, Mr Correia said.

Until all areas can be reached and assessed, it is impossible to say the disaster response effort has turned a corner, he said.

Asked by journalists about people found sheltering in a school along the newly opened main road to Beira who said they had not eaten since the storm, Mr Correia said the aid had to be prioritised according to necessity.

At least they were found and aid is coming, he said. “They can still hang on for a few days.”

He defended Mozambique’s storm warning system, saying people knew weeks in advance that trouble was coming. More than 300,000 were warned in advance, he said, adding: “All reports say the system worked.”

Some residents of Beira and Buzi, however, have said they had heard nothing to indicate the scale of the cyclone and were shocked by the quickly rising waters, and some have expressed anger at the government for not giving more warning.