A 7.1 magnitude earthquake struck off the eastern coast of New Caledonia on Wednesday and generated small tsunami waves, seismologists said, but there were no immediate reports of damage.
The tremor hit at a depth of 27 kilometres (16 miles) in the southern Pacific Ocean, some 231 kilometres from the nearest town Tadine in the lightly populated Loyalty Islands, the US Geological Survey said.
The Pacific Tsunami Warning Center said "small tsunami waves have been observed".
"Persons along coastal areas near the earthquake should be observant and exercise normal caution. Otherwise, no action is required," it added.
Geoscience Australia said shaking would have been felt throughout New Caledonia, but it put the damage radius at 103 kilometres -- well away from land.
New Caledonia, a French overseas territory, is located within the "Ring of Fire", a zone of tectonic activity around the Pacific that is subject to frequent earthquakes and volcanic eruptions.