Authorities in Fiji are assessing the damage after the most powerful storm that swept through the tiny island nation on Saturday night, flattening homes and downing trees. Fijian authorities have confirmed that the category-5 Cyclone Winston has left at least five people dead.

Cyclone Winston brought winds of over 320km/h (200mph), torrential rain and waves of up to 12m (40ft).

It destroyed hundreds of homes and cut electricity lines. There are reports of entire villages flattened.

Unrelenting rain and downed power-lines have hampered relief efforts on Sunday as officials assess the damage and Australian aid agencies offer assistance.

Virgin Australia has announced it will resume flights in and out of Nadi on Monday, while Jetstar and Fiji Airways have cancelled their scheduled flights.

The relief efforts come after the cyclone tore through with winds gusting to 325km/h and waves up to 12m high, cutting communication across much of the country of almost 900,000.

Australian Red Cross worker Susan Slattery said persistent, heavy downpours were complicating early responses to the widespread damage.

“A lot of the communities affected are in low-lying areas and on islands so continued rain will add to the flooding risk,” she told AAP from Suva on Sunday.

“It affects our access into those places that are the hardest hit, including smaller islands that are a long way away.”

Some villages reported that all homes had been destroyed, Jone Tuiipelehaki of the UN Development Programme tweeted after the storm hit.

He said 50 homes in Navaga village on Koro Island had been reported ruined.

“The images that we’re starting to see roll in are terrifying,” Alice Clements, from the UN children’s organisation Unicef in Suva told Reuters news agency. She said she could see a car on a building roof and a small plane stuck in debris.

In the north coast of Fiji’s main island where the cyclone made landfall, a man told Reuters the damage was so extensive that “it looks like a different country”.

George Dregaso, of Fiji’s National Disaster Management Office, told the Associated Press that about 80% of the nation’s 900,000 people were without regular electricity supplies.

Schools have been ordered to shut for a week even though the main airport has been reopened to receive humanitarian supplies.