The Pacific island nation of Vanuatu has lost years of development progress and must "start over" following a powerful cyclone that destroyed or damaged 90 percent of the buildings on the main island of Port Vila, the country's president said Monday.

Baldwin Lonsdale, visibly weary and red eyed from lack of sleep, said in an interview that he and other top government officials were preparing to return home later Monday from Sendai, in northeastern Japan, where they were attending a disaster conference when the cyclone hit.

The government's official toll is eight dead and 20 injured but that looks certain to rise, given the extent of the damage.

Australia, which along with New Zealand and France is providing rescue and relief help, offered transport from Sydney to Port Vila, his staff said.

Save the Children's Vanuatu director Tom Skirrow told AFP news agency the logistical challenges were even worse than Typhoon Haiyan, which struck the Philippines in November 2013, killing more than 7,350 people and ravaging an area a big as Portugal.

The southern island of Tanna, about 125 miles south of the capital, Port Vila, with its 29,000 inhabitants took the full force of the category 5 storm.

Initial reports from aid groups said it had been devastated, along with the main town on the southern island of Erromango, with at least two people reported dead.

A clean-up was under way in Port Vila, where seas were reported to have surged as high as 26 ft.

"Things in Port Vila are improving, people are returning to the market and getting on with the job of starting the clean-up, but the key thing is we still have no contact with other provinces," Tom Perry, from aid agency CARE Australia said by telephone from the capital.

Lonsdale said information from other islands was not available because most communication links were still not working. But the airport in Port Vila has reopened, allowing aid and relief flights to reach the country.

"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."

Officials are struggling to determine the scale of the devastation wrought by the monstrous cyclone that tore through the tiny South Pacific archipelago of Vanuatu, with death counts varying but expected to rise once communications are restored with outlying islands.

Cyclone Pam tore through Vanuatu early Saturday, packing winds of 168 miles per hour, and leaving a trail of destruction and unconfirmed reports of dozens of deaths.

As of Sunday Paolo Malatu, coordinator for the National Disaster Management Office said 20 people were injured in the capital, Port Vila. Earlier, Chloe Morrison, a World Vision emergency communications officer, said Vanuatu's disaster response office told her agency that at least eight people died. She had also heard reports of entire villages being destroyed in more remote areas.

The death toll is widely expected to soar once more information from further afield comes in.

The confusion over the death toll is due largely to a near-total communications blackout across the country. With power lines and phone circuits down, officials in the capital had no way of knowing what the scope of the damage was on the outer islands, where the storm scored a direct hit.

"We haven't been able to communicate outside Port Vila," Malatu said. "At this point, the damage is severe and we haven't had figures of how many houses destroyed. ... It's really bad, it's really bad."

Officials are planning to head to the outer islands Monday in helicopters, small planes and military aircraft to get a better sense of the destruction, Malatu said.

Telephone networks are notoriously spotty in South Pacific island nations such as Vanuatu, particularly in the aftermath of storms. It often takes days before networks can be restored, making it difficult for officials to quickly analyze the breadth of devastation following natural disasters.

Vanuatu's government has declared a nationwide state of emergency, and Australia and New Zealand have sent in relief supplies. Port Vila's airport was damaged by the storm and closed for commercial flights, but the first delivery of supplies arrived Sunday from the Red Cross, Malatu said.

"People are really upset and it's really hard, just because for the last couple of years, we haven't received a really big cyclone like this one," said Isso Nihmei, Vanuatu coordinator for the environmental and crisis response group 350. "Most people right now, they are really homeless."

He came upon one of the storm's victims on Saturday while surveying the damage along the coastline with other relief workers. The group spotted a man lying on the ground, not breathing, and rushed him to the hospital. By the time they arrived, however, he was dead, Nihmei said.

Structural damage across Port Vila was extensive, Nihmei said, with the majority of homes severely damaged or destroyed.

Some residents began cleaning up what was left of their wrecked houses and checking on family members. Relief workers, meanwhile, were trying to get victims to temporary shelters as fast as possible, Nihmei said.

Hannington Alatoa, head of the Vanuatu Red Cross Society, said flyovers by New Zealand and Australian relief teams showed much of the country had been "flattened." At least half of the population, or about 130,000 people, has been affected, Alatoa said in Sendai, Japan, where he and other Vanuatu officials were attending a U.N. conference on disaster risk reduction. He had no accurate information on the numbers left homeless.

"No trees, no foliage, no iron structures standing on the western part of Tanna," Altoa said, referring to one of Vanuatu's southern islands. "Trees blocked the roads. ... People are in great need of water."

Vanuatu has a population of 267,000 people spread over 65 islands. About 47,000 people live in the capital.

The small island nation, located about a quarter of the way from Australia to Hawaii, has repeatedly warned it is already suffering devastating effects from climate change with the island's coastal areas being washed away, forcing resettlement to higher ground and smaller yields on traditional crops.

Scientists say it's impossible to attribute single weather events like Cyclone Pam to climate change.

The cyclone has already caused damage to other Pacific islands, including Kiribati and the Solomon Islands. Authorities in New Zealand are preparing for Cyclone Pam, which is forecast to pass north of the country on Sunday and Monday.

Al Jazeera with wire services