SYDNEY: A huge arc of Pacific nations from New Zealand to Japan went on tsunami alert on Saturday after the giant earthquake in Chile, readying emergency plans instituted after the Indian Ocean disaster of 2004.

The Pacific Tsunami Warning Center warned dozens of far-flung islands and atolls of possible "widespread damage" from waves generated by the 8.8-magnitude earthquake in Chile, which killed at least 78 people.

"Sea level readings confirm that a tsunami has been generated which could cause widespread damage," the Hawaii-based center said. "Authorities should take appropriate action in response to this threat."

Despite their great distance from the quake zone, at-risk nations included New Zealand, Australia, Japan, the Philippines and a string of Pacific archipelagos including Tonga and Samoa.

Chile's remote Robinson Crusoe Island, some 700 kilometres (430 miles) from the mainland, was smashed by a huge wave after the quake, while President Michelle Bachelet also announced a partial evacuation of Easter Island.

New Zealand warned of a wall of water up to three metres (9.8 feet) high potentially hitting outlying islands and part of the South Island, as the country's National Crisis Management Centre went on alert.

The civil defence ministry said the tsunami could hit the country's east coast from 7:05 am (1805 GMT Saturday).

The Joint Australian Tsunami Warning Centre warned of the "possibility of dangerous waves, strong ocean currents and foreshore flooding" along the coast between Sydney and Brisbane.

Officials in the Philippines started planning for possible evacuations.

"No evacuation order is in effect but communities along the east coast of the country are advised to wait for further information and to prepare for possible evacuation," the Philippine Institute of Volcanology and Seismology said. "Coastal areas fronting the Pacific Ocean... should keep watch."

Jake Phillips, a forecaster with Australia's Bureau of Meteorology, played down the risk of major flooding in heavily populated coastal areas.

"But there is a marine threat and that would include anyone out boating or rock fishermen," he said.

Coastal residents were urged to stay away from the shoreline, while any boats should be taken back to harbour and strongly secured.

Memories are still raw in Samoa, American Samoa and Tonga of a terrifying tsunami that trashed entire villages in September, leaving 184 dead and sparking a major international relief operation.

Just a week later, thousands fled South Pacific coastal areas after a rapid succession of powerful earthquakes off Vanuatu. The Pacific "Ring of Fire" region is often hit by seismic activity caused by massive tectonic movement.

The latest warnings evoked memories of the 2004 Boxing Day tsunami which killed more than 220,000 people around the Indian Ocean.

That was on the other side of Asia, but Pacific nations subsequently stepped up their own tsunami preparations in concert with the US government, with a system of electronic buoys in place to give real-time warning of giant waves.

Australian officials said any tsunami would not be seen for several hours with effects only visible from about 8:15 am on Sunday (2115 GMT Saturday).

If generated, a tsunami would reach the east coast of Japan around noon Sunday (0300 GMT Sunday), according to the country's meteorological agency.

"We would like people to be fully on alert for related information," agency official Yasuo Sekita told a hastily arranged news conference, as Prime Minister Yukio Hatoyama ordered his government to be ready for relief work.

There were no tsunami alerts immediately issued in Indonesia and Taiwan, but officials said they were monitoring closely.