A magnitude 8 earthquake struck around 8.28am NZ time at a depth of 10 km, triggering an alert for much of the south Pacific region.
The Pacific Tsunami Warning Centre said hazardous tsunami waves were possible within the next three hours along the coastlines.
Waves reaching one to three metres above the tide level are possible along some coasts of French Polynesia.
Waves reaching 0.3 to 1 metre above the tide level are possible for some coasts of American Samoa, the Cook Islands, Fiji, New Caledonia, New Zealand, Niue, Pitcairn, Solomon Islands, Tonga, Vanuatu and Wallis and Futuna.
Samoan authorites have issued a tsunami watch for all low-lying coastal areas. People living in these areas are advised to stay away from beaches.
New Zealand authorities have already directed people on the East Coast of the North Island from the Bay of Islands to Whangārei, from Matata to Tolaga Bay including Whakatāne and Opotiki and Great Barrier Island to move immediately to higher ground.
The advisory follows an earlier 7.4 magnitude quake in the same area.
That event occurred at 6:41am New Zealand time, at a depth of 10 kilometres.
The earthquakes off the Kermadecs follow another large quake in New Zealand waters this morning off the North Island's east coast.
The 7.1 magnitude Te Araroa quake at 3:15am caused evacuations along much of the North Island's east coast.