The storm smashed into Vanuatu over the past 24 hours, leaving reports of “complete devastation” in its wake.
The maximum category five cyclone hit Vanuatu late on Friday and early indications suggest widespread damage, including in the capital in Port Vila, with fears dozens of people could have died across the country.
“While it is too early to say for certain, early reports are indicating that this weather disaster could potentially be one of the worst in Pacific history,” New Zealand executive director Vivien Maidaborn said in a statement.
“The sheer force of the storm combined with communities just not set up to withstand it, could have devastating results for thousands across the region.”
Powerlines and communications are down for much of Vanuatu and the Port Vila airport remained closed. Unicef said its biggest concerns were now about ensuring shelter for those impacted.
Unicef’s Pacific communications specialist Alice Clements, who is in Port Vila, said it was clear that the full force of Cyclone Pam was dramatically worse than predicted and would be a catastrophe for Vanuatu.
“I saw the sliding doors from my three storey hotel room completely blow away – it was terrifying,” she said.
“We have some very unconfirmed reports of casualties from the outer islands as well but we’re waiting to get official confirmation on those, which is very sad news if it’s true.”
Aid agencies are mobilising to deal with the situation, and Unicef said it was working with national disaster authorities in Vanuatu, Fiji and Solomon Islands to offer support.