The Christchurch mosque attacker who shot 51 people dead and wounded 40 more has been sentenced to life in prison without parole.

Brenton Tarrant, 29, went on a shooting rampage at two separate mosques on March 15 last year, murdering men, women and children in a devastating 19-minute attack.

Ahead of the sentencing, Judge Cameron Mander described Tarrant’s actions as ‘inhuman’ and insisted he 'showed no mercy’.

He said: "Your crimes are so wicked that even if you are detained until you die, it will not exhaust the requirements of punishment."

When explaining his decision to incarcerate Tarrant for life without parole, Mander added: "If not here, then when?"

This is the highest sentence possible in New Zealand as the country does not carry the death penalty, and the first time it has been handed down.

After hearing the news, Prime Minister Jacinda Ardern said Tarrant would now have ‘no notoriety, no platform... and we have no cause to think about him, to see him or to hear from him again’.

She added: "Today I hope is the last where we have any cause to hear or utter the name of the terrorist." 

The sentencing was met with widespread approval from the families of the victims and those who survived the shootings.

Irfan Yunianto, a survivor of the attacks, said: "I was at the shooting location. Many of my friends died. I also saw with my own eyes how my friends were trying to save the victims.

"I accept the court decision with good grace. Following this trial has been really hard, but I still watched it online. 

"After the verdict was reached I felt so relieved because the court finally delivered its final verdict."