Initial relief supplies for Vanuatu are just a "drop in the ocean" of what is needed, according to one aid worker.
It comes after Cyclone Pam devastated the Pacific island nation over the weekend.
Alice Clements from Unicef is in the capital city of Port Vila, and she says there are a total of 83 islands in the country that need to be assessed.
She said: "More than 60 of these are uninhabited, so if you were to imagine 60-plus emergencies on 60-plus islands, it is unbelievably complex.
"So many of these islands don’t have landing strips, they can only be accessed by boat or helicopter.
"It's fantasitc that these intial shipments of relief are coming through, but this is a drop in the ocean."
An plane carrying aid has flown out of the UK today to help relief efforts there.
The load, containing 1,640 shelter kits and 1,900 solar lanterns with phone chargers, comes after the British Government announced a £2m donation towards UN humanitarian aid efforts.
Cyclone Pam tore through the archipelago of islands with winds of up to 155mph and heavy rainfall causing widespread destruction.
A C-17 transport plane flew out from RAF Brize Norton this morning bound for the Royal Australian Air Force base at Amberley, Australia, before linking up with international agencies.
A humanitarian expert from the UK's Department for International Development has also been deployed to offer advice and assistance on field assessments, while the RAF crew will carry out support flights over several days.
Britian's International Development Secretary Justine Greening said: “The terrible effects of Cyclone Pam are now clear and many people are in urgent need of relief.
“The Royal Air Force’s swift and invaluable support will ensure victims of the cyclone get the help they need to start putting their lives back together.
“Families’ homes have been destroyed and power supplies are down. Our emergency shelter kits and solar lanterns will help meet people’s basic needs and Britain stands ready to assist further.”
The country’s president Baldwin Lonsdale estimated the cyclone had destroyed or damaged 90% of the buildings in the capital of Port Vila.
He said: “This is a very devastating cyclone in Vanuatu. I term it as a monster, a monster. It’s a setback for the government and for the people of Vanuatu. After all the development that has taken place, all this development has been wiped out.”
“So it means we will have to start anew again.”