A tsunami threat has been issued for Lord Howe Island, which is about 550 km east of Australia's mainland, the Australian Bureau of Meteorology said.
Earlier in the day, a tsunami warning was issued for New Zealand, New Caledonia, Vanuatu, and some other nations in the South Pacific following a 7.7-magnitude quake that struck east of Vao in New Caledonia at a depth of 10 km.
"We expect New Zealand coastal areas to experience strong and unusual currents and unpredictable surges at the shore following a magnitude 7.7 earthquake," the disaster agency said.