A MAGNITUDE 8.0 earthquake has struck off the east coast of Papua New Guinea, according to reports.

The magnitude-7.9 quake struck 46 kilometres east of Taron in Papua New Guinea, the US Geological Survey said.

The USGS initially said the quake’s magnitude was 8.0, but later downgraded the strength.

The New Zealand Ministry of Civil Defence & Emergency Management also issued an official tsunami warning for New Zealand, before later tweeting there was “no threat” to the country, and cancelling the warning.

According to the Joint Australian Tsunami Warning Centre there is no tsunami threat to the Australian mainland, islands or territories.

However, hazardous tsunami waves could hit coastal areas of Papua New Guinea, the Solomon Islands, Indonesia, Nauru and other islands in the three hours following the quake, the Pacific Tsunami Warning Centre said.

The quake occurred 60 kilometres east of Taron on New Ireland island at 9.51pm AEDT on Saturday at a depth of 73.4 kilometres.

The quake rattled residents near the epicentre on the island of New Ireland, but was not felt in Papua New Guinea’s capital, Port Moresby, said Mathew Moihoi, an official with the Geophysical Observatory.

The quake knocked items off shelves and caused a blackout in the town of Kokopo in northeastern Papua New Guinea, Taranu said. But there were no reports of widespread damage in the town.

A tsunami measuring less than one metre hit the coast of the island shortly after the earthquake, said Felix Taranu, seismologist with the Geophysical Observatory in the capital, Port Moresby.

There were no immediate reports of damage from the tsunami or the quake, though officials were still working to contact people on the island, he said.

Papua New Guinea sits on the Ring of Fire, the arc of seismic faults around the Pacific Ocean where earthquakes are common. It’s a vast area where about 90 per cent of the world’s earthquakes occur, according to the USGS.

The ring, which actually is shaped more like a horseshoe, includes more than 400 underwater volcanoes and stretches 400 kilometres from New Zealand, past Japan, across the Bering Strait and down to the tip of South America.

(news.com.au)