|Honolulu's high-rise hotels were spared by tsunami waves which surged ashore on Friday. [Getty]
Islands and coastal regions across the Pacific Ocean readied themselves for a tsunami triggered by Friday's massive earthquake in Japan but initial reports suggest Hawaii, Indonesia and the Philippines have escaped unscathed.
Tsunami alerts were in place from Russia and Canada's British Columbia as far as Fiji and Papua New Guinea as the American islands of Hawaii became the first to be hit by the surging waters.
Hundreds of people have been killed along Japan's northeastern coastline, close to the 8.9-magnitude quake's epicentre, but there are fears that low-lying islands could be flooded completely.
"Our biggest concern is the Asia and Pacific region, where developing countries are far more vulnerable to this type of unfolding disaster. The tsunami is a major threat," said Paul Conneally, spokesman for the International Federation of Red Cross and Red Crescent Societies, the world's biggest disaster relief network.
"At the moment, it is higher than some islands and could go right over them."
Authorities in French Polynesia woke residents in the early hours of the morning on Friday to order them to move to high ground. Waves up to three metres high could hit the Marquesas islands, the AFP news agency said.
In another French Pacific territory, New Caledonia, authorities ordered residents in northern parts of the main island and on the nearby Loyalty Islands "to evacuate their homes and reach high ground".
The American islands of Hawaii were among the first to be hit as two-metre waves surged ashore at Honolulu's Waikiki beach.
Civil defence officials ordered coastal areas evacuated and police with bullhorns urged residents to move to higher ground. But there were no reports of damage and waters stopped short of the resort city's shoreline high-rise hotels.
Meanwhile, two US Navy submarines broke their moorings in Guam after being hit by the wave, but tug boats were able to tow the vessels back to the pier. No damage was reported, either to those submarines, or the larger US Navy fleet in Hawaii.
"I think the enormous fears that that were there hours ago, for some of us hours ago, has diminished greatly, which is quite a relief for all of us," said White House chief of staff Bill Daley.
But evacuations were under way from some counties in California as officials warned that northern regions of the state could experience waves up to two metres high.
Manila tsunami alert lifted
There were no reports of major damage in southeast Asia, despite tsunami warnings along Indonesia and the Philippines' northeastern coastlines.
Thousands heeded warnings to evacuate their homes in Indonesia -- a country which suffered massive casualties in Aceh province in the 2004 tsunami which killed more than 200,000 people.
Meteorological officials said waves only slightly higher than normal had hit the North Maluku islands and said no significant damage had been reported. But they warned that a second, larger tsunami could be on the way.
In Manila, the Philippines' capital, the military was ordered to help evacuate areas at risk on the east coast but civil defence officials lifted a tsunami alert after small waves hit its Pacific coast.
Mexican ports shut down
In southern Mexico, authorities shut down three ports, including the oil exporting terminal of Salinas Cruz. Six empty oil tankers were ordered to move away from the coastline, while beach resorts further north were closed down and evacuated.
Governments in Central America were also on alert. In Honduras, the police and army were ready to carry out evacuations where needed, while Guatemala and Costa Rica were telling small ships to stay out of the water.
Further south, Ecuadorean President Rafael Correa declared a state of emergency across the Andean nation, declaring schools closed and urging coastal and island residents to evacuate fast to higher areas hours ahead of the expected arrival of the waves at 12 am GMT.
The Galapagos Islands, a popular tourism attraction and wildlife sanctuary lying almost 1,000km off the mainland, were also placed on alert with flights cancelled and evacuations under way.
"Hopefully nothing will happen but we should be prepared for anything," said Correa. He said the waves were expected to reach Galapagos at 22G and the mainland at 00G. Flights to the Galapagos, Esmeraldas and Manta have been canceled. Local media saying evacuations have begun in Esmeraldas and Galapagos.
Residents on the Easter Islands were moved to the Chilean territory's airport, 45 metres above sea level,although the waves were not expected to reach the islands until 8 pm GMT.
Chilean authorities on the mainland also moved some patients from hospitals along the country's southeastern coast while Colombia's government placed 16 low-lying towns and cities on alert for a possible evacuation.