Another strong earthquake has struck the Pacific nation of Vanuatu, but there was no tsunami threat and no immediate reports of damage or injuries.

A third earthquake, measuring 6.9 on the Richter Scale, has struck off the coast of Vanuatu. Source: Google Maps

The magnitude-6.9 quake struck just after 3.30pm today (NZ time), 109km west of the village of Sola, and 453km north-west of the capital, Port Vila.

It is the third strong earthquake to strike Vanuatu since Sunday, although none have caused problems.

Vanuatu National Disaster Management Office Director Shadrack Welegtabit said he didn't feel the quake in the capital and hasn't received any reports that it has affected the island nation.

He said he wasn't sure what had triggered the recent spate of earthquakes.