A strong 6.3 magnitude quake struck off the Pacific island nation of Vanuatu on Friday, the US Geological Survey said. The tremor hit about 358 kilometres (222 miles) north-northwest of the capital Port Vila at a depth of about 180 kilometres, USGS said. Hilaire Bule, a journalist at the Vanuatu Independent, said the tremor was not felt in Port Vila. "We never felt anything here at all," he told AFP. Geoscience Australia seismologist Steve Tatham said the offshore quake would not pose a tsunami risk to Australia. "The magnitude isn't there, it's also relatively deep," he said. In April, a 6.5-magnitude earthquake struck off the coast of the South Pacific island which lies on the so-called "Pacific Ring of Fire", a zone of frequent seismic activity caused by friction between shifting tectonic plates. "Vanuatu provides us with a good number of significant sized earthquakes so this isn't out of character at all," Tatham said. "This... usually doesn't produce any sea level disturbances."