Tonga police have told the New Zealand High Commission that the confirmed death toll stands at two but with communications in the South Pacific island nation cut, the true extent of casualties was not clear.
Tonga’s main airport, Fua’amotu International Airport, was not damaged in Saturday's eruption and tsunami but heavy ashfall is preventing full operations, hampering international relief efforts.
"The priority now will to be get supplies to Tonga, and the biggest constraint on that at the moment ... is the airport. There is still a significant amount of ash," Australia's Minister for the Pacific Zed Seselja said.
Tongan officials were planning to evacuate people from outer islands where conditions were "very tough, we understand, with many houses being destroyed in the tsunami", Seselja said.