Britain has pledged up to £6 million of aid to send humanitarian relief to the hundreds of thousands of people affected by Cyclone Idai in Mozambique and Malawi.
International Development Secretary Penny Mordaunt said a team of experts was on the ground in Mozambique helping to co-ordinate the UK's response.
Filipe Nyusi, the president of Mozambique, said more than 1,000 people are feared dead in the country four days after the cyclone hit.
Tents and thousands of shelter kits will be sent to the country on Tuesday, and Ms Mordaunt said the UK stands ready to "scale up our support if needed".
Around 600,000 people in Mozambique and 900,000 in Malawi are thought to have been affected by the cyclone, according to United Nations estimates.
Entire villages were submerged and bodies left floating in the floodwaters in the wake of the natural disaster.
Ms Mordaunt said: "I have made £6 million of UK aid available to help meet the immediate needs of people who have lost everything.
"We have deployed a UK team of Dfid experts who are now on the ground in Mozambique helping to co-ordinate the UK's response to this disaster, and we hope to have vital UK aid supplies in the region shortly. We stand ready to scale up our support if needed.
"The images of loss and devastation following this deadly cyclone and extreme weather are shocking. The people of Mozambique, Malawi and Zimbabwe should know that they are firmly in our thoughts at this difficult time, and that the UK stands by their side."
Cyclone Idai made landfall close to the port city of Beira on Thursday with winds of up to 106 mph, but aid teams only reached the city on Sunday.
The Red Cross said that 90 percent of Beira, a city of 500,000, had been damaged or destroyed.
Beira has been severely battered by the cyclone which cut off electricity, forced the airport to shut down and closed road access to the city, said the International Federation of Red Cross and Red Crescent Societies on Monday.
Cyclone Idai first hit Beira last week and then moved inland spreading heavy winds and rainfall to Zimbabwe and Malawi.
The scale of the damage to Beira is "massive and horrifying," said Jamie LeSueur, who led a Red Cross aerial assessment of the city. The team had to view the city by helicopter because roads were flooded, he said.
"The situation is terrible. The scale of devastation is enormous. It seems that 90 percent of the area is completely destroyed," said Mr LeSueur.
