Misa Telefoni said the powerful waves which have killed at least 36 people in the archipelago had smashed into upmarket island resorts off the west coast of the main island of Upolu.

"We've heard that most of the resorts are totally devastated on that side of the island," he told Australian Associated Press.

"We've had a pretty grim picture painted of all that coast," he added.

His comments came as officials confirmed that two South Koreans and an Australian had died in the disaster triggered by an 8.0 magnitude earthquake early Tuesday.

New Zealand said one of its nationals was feared dead and that more tourists could have died as the waves hit during a busy school holiday period.

"We have one reliable but as yet unconfirmed report of a New Zealand death," acting Prime Minister Bill English said.

"We are of course concerned that there may be more given that the tsunami struck an area in Samoa where there are several resorts, and it's during the school holidays when a number of our Samoan-New Zealand families go back to Samoa."

Australian officials have confirmed three nationals were injured in the disaster and six missing and that they have provided assistance to Britons and Canadians affected by the tsunami.

Australian Foreign Minister Stephen Smith said the southern region of Samoa, which includes major tourist facilities, appeared worst hit by the surge of water.

"In Samoa it's really especially the southeast of the island that's been hit and that's unfortunately where a lot of both the luxury resorts and the budget resorts are, and of course we're concerned there may be Australians holidaying there," he said.

Tourism is a major industry for Samoa, which boasts a year-round warm climate, pristine beaches and lush tropical rainforests.