Papua New Guinean authorities are trying to confirm damage reports and work out if a tsunami was generated after a powerful earthquake struck a remote island in Papua New Guinea's east this morning.

Key points: The quake was initially recorded with a magnitude of 7.3, but was downgraded

The quake was initially recorded with a magnitude of 7.3, but was downgraded A warning of 30 centimetre tsunami waves was cancelled

A warning of 30 centimetre tsunami waves was cancelled At least two aftershocks greater than magnitude-5 were recorded

The quake hit part of New Britain, about 200 kilometres south-west of the town of Rabaul at a depth of almost 40km, just before 7:00am local time, the United States Geological Survey reported.

"We felt the earthquake a bit, but it was not too strong," Constable Roy Michael said, speaking by phone from Rabaul police station.

He said there was no damage in the town, but officers had not yet been able to contact villages closer to the epicentre.

The Pacific Tsunami Warning Centre said there was no longer a threat of tsunami waves after the quake.

It earlier warned that waves up to about 30 centimetres were possible within 300 kilometres of the epicentre.

Chris McKee from Papua New Guinea's Geohazards Management department in the capital, Port Moresby, said authorities were still trying to confirm reports of damage or if a tsunami was generated.

Australia's Tsunami Warning Centre said its coastlines were not at risk.

Pacific Tsunami Warning Centre oceanographer David Walsh earlier said any tsunami from the earthquake would only affect areas immediately around the epicentre.

But scientists do not have any tide gauges close to where the earthquake happened, so are unable to say at this point whether tsunamis have been generated.

He said areas farther away were unlikely to be affected because the earthquake was not "terribly large" and many regions were shielded by land masses and islands.

The quake was initially recorded with a magnitude of 7.3 but was downgraded.

At least two aftershocks with a magnitude greater than 5 shortly followed.

In March, a magnitude-6.6 quake struck nearby with no casualties or damage reported.

Papua New Guinea, one of the world's poorest countries, sits on the geologically active Pacific Ring of Fire and is still recovering from a magnitude-7.5 quake that hit some 900km to the west in February, killing at least 100 people.

Separate quake rocks Bali

Also on Thursday, a magnitude-6.0 earthquake struck just off the popular island of Bali, Indonesia, where the International Monetary Fund and its sister lending organisation, the World Bank, were holding annual meetings until Sunday.

Indonesian authorities said at least three people were killed and four injured in the quake.

Some tourists and residents ducked outdoors as a precaution but then went back to sleep when there was no tsunami warning.

Indonesia is still reeling from an earthquake and tsunami on the island of Sulawesi that killed more than 2,000 people. Officials say more than 80,000 people are living in temporary shelters or otherwise displaced.

Wires/ABC