Australia's prime minister Scott Morrison has revealed he's "open to discussions" on whether the mosque gunman Brenton Tarrant should serve out his punishment in Australia.
Australian-born Tarrant, who arrived in New Zealand in 2017, was yesterday sentenced to life imprisonment without parole in this country's worst gun massacre.
"Whether he is held in Australia or New Zealand, we are open to that discussion,'' the Australian Prime Minister revealed on Sunrise.
"It has a lot of implications, these sorts of decisions. The Prime Minister of New Zealand and I will talk about those issues.
"Most of all we are concerned about what the views of the families would be for those affected and we want to do the right thing by them. There is been no request made for that I should stress."
Whatever the outcome, Morrison said he agreed with New Zealand Prime Minister Jacinda Ardern that the terrorist should be "locked up forever" and never see the light of day again.
Speaking on 2GB radio, Morrison revealed he had held his first discussions with Ardern about the convicted killer on Thursday afternoon.
But he cautioned any broadbased prison swap arrangement would have big implications.
"We have many New Zealanders in prisoners here,'' he said. "As you know we send them back when they have served out their sentence.
"This is a very rare case. The Prime Minister and I are open to having discussions about this. But there's been no request made.
"But we would both want to know particularly what the families thought of this."
The costs to keep the killer behind bars until his death are likely to run into the millions, currently costing over $4930 a day due to the extra levels of security.
Yesterday, New Zealand's Deputy Prime Minister Winston Peters demanded Australia take back the mass murderer so that his victims' families are not forced to pay the "astronomical" cost of his incarceration.
"Now is the time for Australia's Minister of Home Affairs, Peter Dutton, to receive and carry out the terrorist's sentence in Australia," Peters said.
"The Islamic community and all of New Zealand has already suffered enough without having to pay astronomical prison costs to keep him safe in our prison system."
It came after Ardern said Tarrant's crime was one that "New Zealand has never seen the likes of before and this is a sentence we've never seen before".
"It gave me relief, to know that person will never see the light of day," she said.
"The trauma of March 15 is not easily healed, but today I hope is the last where we have any cause to hear or utter the name of the terrorist behind it. His deserves to be a lifetime of complete and utter silence."
On Thursday, Morrison had indicated his view that Tarrant should serve out his sentence in New Zealand.
"This is not a matter which the Prime Minister Ardern has raised with me,'' Morrison said.
In fact, Ardern has previously raised the prospect of a prison swap of Tarrant but only after "justice is done here first".