A powerful earthquake struck waters off Vanuatu in the South Pacific on Saturday, prompting a tsunami warning for nearby coastal areas before the alert was lifted, according to seismic monitoring agencies.

The United States Geological Survey (USGS) initially reported a magnitude of 7.2, placing the epicentre about 200 kilometres (124 miles) west of Sola, Vanuatu, at a depth of 10 kilometres (6.2 miles).

The USGS later reported the magnitude as 6.9, while several aftershocks were recorded in the area, according to the Associated Press.

The Pacific Tsunami Warning Center issued an alert following the shallow earthquake, warning that potentially hazardous tsunami waves could affect coastlines within 300 kilometres of the epicentre. The warning was subsequently rescinded.

There were no immediate reports of casualties or significant damage, although authorities and monitoring agencies continued to assess the situation.

Vanuatu, an island nation in the South Pacific, lies along the Pacific Ring of Fire, a seismically active zone where tectonic plates interact and earthquakes and volcanic eruptions are common.

The impact of an earthquake depends on factors including its magnitude, depth, distance from populated areas and local ground conditions. Shallow, powerful undersea earthquakes can generate tsunamis capable of threatening coastal communities.

Authorities have urged residents in affected areas to follow official advisories as further information becomes available. (ILKHA)