The quake's epicentre was 424 km east of Tadine, New Caledonia, and was at a depth of 10 km, EMSC said.
The quake, which was upgraded from an earlier magnitude of 7.1, followed at least three other earthquakes in the region with magnitudes ranging from 5.7 to 6.1 in a span of just over an hour.
The U.S. Tsunami Warning System said a tsunami watch was in effect for American Samoa and that there was potential for tsunamis in other regions including Vanuatu, Fiji, New Zealand.
