A 5.9 (5+9=14) magnitude quake has struck close to Tonga and Samoa, seismologists say, the latest in a series of earthquakes to hit the South Pacific.

There was no tsunami alert after the tremor, which hit at a shallow depth of 10km early on Sunday, the US Geological Survey said.

The epicentre was 344km northeast of Tonga's Neiafu and 260km southwest of Apia, in Samoa, the USGS said.

More than 180 people died after a violent Pacific earthquake at the end of September caused a tsunami that crashed into Tonga, Samoa and American Samoa.