The US government's NWS Pacific Tsunami Warning Center said "hazardous tsunami waves" were forecast for some coasts
A 7.7-magnitude earthquake struck in the South Pacific on Thursday, generating a tsunami that threatened island nations in the region.
The quake struck at just after midnight on Thursday local time (1320 GMT on Wednesday) about 415 kilometres east of Vao in New Caledonia at a depth of 10 kilometres, according to the US Geological Survey.
The US government's NWS Pacific Tsunami Warning Center said "hazardous tsunami waves" were forecast for some coasts.
It said waves reaching between 0.3 and one metre above the tide level were possible for Fiji, New Zealand and Vanuatu.
A wave of 0.3 metres struck Fiji, according to the Twitter feed of the island nation's seismology department.
It provided no further details.
The Australian Bureau of Meteorology also confirmed in a tweet that a tsunami had been generated.
The bureau warned of a threat to Lord Howe Island, which is about 550 kilometres east of Australia's mainland.
The New Zealand National Emergency Management Agency released a statement telling people in coastal areas to move away from waterfronts.
"We expect New Zealand coastal areas to experience strong and unusual currents and unpredictable surges at the shore following a magnitude 7.7 earthquake," the disaster agency said.
"People in or near the sea in the following areas should move out of the water, off beaches and shore areas and away from harbours, rivers and estuaries."
The affected areas included the far north of New Zealand's north island, the Great Barrier Island east of Auckland and a stretch of coast along the country's east.
There were no initial reports of casualties or damage from the tsunami or the quake, which was initially recorded by USGS at magnitude 7.5 before being revised to 7.7.
The Pacific "Ring of Fire", where tectonic plates collide, experiences frequent seismic and volcanic activity.
In 2018, a 7.5-magnitude quake and subsequent tsunami on Indonesia's Sulawesi Island left more than 4,300 people dead or missing.
A 9.1-magnitude quake struck off the coast of Indonesia's Sumatra Island in 2004, triggering a tsunami that killed 220,000 throughout the region.
The death toll included around 170,000 in Indonesia -- one of the deadliest natural disasters in recorded history.