Along with the Langfords from Sydney, they're among the many families finally hearing the confirmation of their loved ones' deaths, a week after they were caught up in the deadly eruption off New Zealand's North Island.

After an agonising wait, Mr Elzer's family released a statement through the Department of Foreign Affairs on Monday evening, saying the death of their "cherished" son, brother and uncle had been officially confirmed earlier that day.

"It has brought our family great relief to know that Rick was with the love of his life Karla Mathews at the time of the eruption and that they were together when they passed," they said.

"Together with Karla's family, we will now be able to bring them home."

The family said they received the news just moments before they observed a minute's silence on HMNZS Wellington followed by a Haka on Monday, as they looked upon the island where Mr Elzer died.

"Our family is absolutely heartbroken and our big sister will be incredibly missed," the Mathews' family said in a statement on Monday.

"We have an enormous sense of relief that she has finally been found and we patiently wait with the Elzer family for news of Karla's partner Rick, so we are able to bring them home together."

The previously presumed deaths of Anthony and Kristine Langford were also confirmed in the past two days, taking the official toll from the tragedy to 16, which is expected to rise.

Their daughter Winona, 17, is still unaccounted for, while son Jesse, 19, is recovering in hospital.

The Langfords were remembered as "loving parents" to their teenagers and a "wonderful couple".

"They will be greatly missed by all who knew them."

Some 47 people, including 24 Australian citizens and four permanent residents, were on the island when the volcano erupted.

After six bodies were retrieved from White Island, two more remain on the site, one of whom is believed to be an Australian.

Meanwhile, travellers on the Ovation of the Seas cruise ship returned to Sydney on Monday morning in a sombre mood a week after the eruption that took the lives of some of their fellow passengers.

One passenger called Joanne became tearful as she talked to reporters at Circular Quay about the passengers who didn't come home.

"They're people, people that went on my holiday of a lifetime that I've waited 50 years for and they never got to come home ... dreadful."

Joanne told how she'd been upset seeing their suitcases being removed from the ship.

"(It) just broke my heart," she said.

Another passenger said the people on the ship were left in the dark as the tragedy unfolded.

"I've got a son that's 17 who lost two friends that he made. We didn't know how many people were missing," he told reporters after disembarking.

Three more Australians were confirmed dead by NZ Police on Monday: Jessica Richards, 20, from Brisbane; Mr Elzer and Ms Mathews' friend from Coffs Harbour Jason Griffiths, 33, and Martin Hollander, 48.

The other Australians to have been confirmed as victims are: Adelaide schoolgirl Zoe Hosking, 15; her stepfather Gavin Dallow, 53; while Mr Hollander's sons Matthew, 13, and Berend, 16, who were US citizens, were also confirmed dead.

An Australian man, whose family asked that he not be named, died in a Sydney hospital on Sunday.

Another 12 people are being treated in Australian hospitals after being repatriated with severe burns.

Foreign Minister Marise Payne flew to New Zealand on Monday to meet with Prime Minister Jacinda Ardern to thank the first responders and other who saved lives.

Australian Associated Press