A warning for "hazardous tsunami waves" was issued briefly for coastal regions within 300km of Wau in Papua New Guinea's northeast after a 7.0 magnitude earthquake struck the region, the US Pacific Tsunami Warning Center says.
The quake struck about 12.50pm local time (same time AEST) at a depth of 85km, according to the US Geological Survey, and struck offshore 18km east-southeast of Wau.
The Pacific Tsunami Warning Center initially issued a tsunami warning but said about an hour later the danger had passed.
There were no immediate reports of casualties or damage from the quake, which was initially recorded at 7.3 but later adjusted, and the PNG National Disaster Centre declined to comment until it had received a briefing.
Wau is an inland former gold mining town with a population of about 5000, about 150km southwest of PNG's second-largest city, Lae.
A person who answered the phone at the Lae City Hotel said they had felt the quake but there was no property damage.