Australian Labor Party leader Bill Shorten says there is "no hole in the ground big enough" for the man who carried out the Christchurch massacre.
Speaking to the Herald, Shorten said Australia as a whole was "shocked by the act of evil" committed by the man.
Prime Minister Jacinda Ardern has confirmed the man, who was this morning charged with murder, is an Australian citizen.
Although he said the massacre was tragic regardless of who pulled the trigger, "the fact that it was an Australian who did it was even worse."
Asked why, he said because Australians "love New Zealanders".
"New Zealanders and Australians couldn't be closer."
Ardern was asked today if the man should be deported back to Australia.
She said that was an issue she was "seeking further advice on".
"Obviously we will want to ensure that this individual faces the charges against them here in New Zealand, in the first instance."
Asked the same question, Shorten said if he's convicted there was "no hole in the ground big enough for him," he said, before clarifying he meant prison cell.
He said he agreed with comment made by Labor's Shadow Foreign Affairs Minister Penny Wong that the man's action do not represents Australia.
"Australians generally right across the continent have said 'oh my God, how can this be?" He said, describing what he called a "collective shock".
He said hate speech needed to be clamped down on.
"Not all right wing right wing extremist hate speech ends in right wing, extremism violence; but all right wing extremist violence starts with right wing extremism hate speech."
Shorten said all mainstream political parties need to call out hate speech when they see it - "we can't nurture it".
"Freedom of speech does not mean the ability to demigrate hatred and violence against minorities."
He praised Prime Minister Jacinda Ardern's moves towards tighter gun reform in New Zealand in the wake of the massacre.
Shorten said the question now on everyone's lips would be "could this have been prevented".
The man was not on a watch list in either Australia or New Zealand - Ardern said today that was because he did not have a criminal record.