The Pacific Tsunami Warning Centre (PTWC) says the tsunami threat has passed after a strong, shallow earthquake hit off the coast of New Caledonia.

Key points: The earthquake struck about 310 kilometres from New Caledonia's capital

The earthquake struck about 310 kilometres from New Caledonia's capital 1-3-metre waves were forecast, but Vanuatu is not expecting "destructive" waves

1-3-metre waves were forecast, but Vanuatu is not expecting "destructive" waves No threat alert was issued for Australia

The US National Tsunami Centre said the magnitude-7.5 quake struck at a depth of around 10 kilometres just after 3:00pm (local time), about 168 kilometres east of the nearest population centre, Tadine, on New Caledonia's Loyalty Islands.

The PTWC warned there was a possibility of "hazardous tsunami waves" between 1 and 3 metres high hitting Vanuatu and New Caledonia.

It confirmed "tsunami waves have been observed" at about 3:45pm (AEST), but ultimately their impact on land was limited.

Vanuatu Daily Post media director Dan McGarry said he had heard reports of three small wave surges hitting the southern-most island of Aneityum.

He said the waves travelled only a couple of metres beyond the normal tidal waves and that everybody was fine on the island.

No threat alert was issued for Australia as a result of the quake. ( Supplied: USGS )

McGarry said he felt the quake where he is based in Vanuatu's capital, Port Vila, as a mild shaking.

"We get a lot of earthquakes every year," he said.

"The tsunami warning was what was different this time, though."

Vanuatu's government released a statement saying it was not expecting a "destructive tsunami".

Reports from locals on Aneityum said waves came about 12 metres up the beach and damaged some gardens.

Further north, on the island of Aniwa, Issac Taseru told the ABC a few houses had been damaged but there were no injuries.

The earthquake's epicentre was about 310 kilometres away from New Caledonia's capital, Noumea.

"That is pretty far away," USGS's Rafael Abreu said.

Crops were damaged as small waves hit Vanuatu. ( Supplied: Hudson Mataiyo )

"We wouldn't expect to see any significant damage from that far away from the ground-shaking related to this event."

According to PTWC, any waves that hit Australia as a result of the tremor would be less than 30 centimetres tall, while there could be waves of up to a metre for Fiji.

At least five aftershocks also hit, ranging in magnitude from 5.6 to 7.

New Caledonia sits on the Pacific "Ring of Fire" — the arc of seismic faults around the Pacific Ocean where most of the world's earthquakes and volcanic activity occur.

ABC/AP