A strong 6.3-magnitude earthquake struck Papua New Guinea's northern coast on Wednesday, the US Geological Survey said, but there were no immediate reports of damage or tsunami activity. The quake hit at 1:55pm (0355 GMT) with an epicentre about 31 kilometres (19 miles) east-southeast of the coastal town of Wewak, at a depth of 10 kilometres (6.2 miles), the USGS said.

The tremblor was not expected to generate a tsunami, said assistant director of the PNG government's Geological Survey Department Chris McKee.

"I've had no reports of any damage and a 6.3 magnitude quake is unlikely to generate a tsunami," he told AFP.

Papua New Guinea was last hit by a major earthquake on March 25, when a 6.0 magnitude quake hit 117 kilometres (73 miles) south-southwest of Rabaul, without significant damage.

The impoverished country is home to many active volcanoes and sits on the Pacific "Ring of Fire" where several tectonic plates collide. The region is frequently rocked by earthquakes.