A 17-year-old New Zealand youth was sent to prison Wednesday for 15-and-a-half years for murdering a taxi driver who was a refugee from Afghanistan.

Shannon David Boyes-Warren, was 16 at the time he stabbed Abdulrahman Ikhtiari, 39 and a father of five, to death with a 13-centimetre knife, after an evening of drinking in the South Island city of Christchurch.

Judge Christine French gave Boyes-Warren the mandatory life sentence in the Christchurch High Court and imposed a non-parole period of 15-and-a-half years.

Randall Legion Wiremu Brown, 21, held Ikhtiari while his friend stabbed him. Brown admitted to manslaughter and was jailed for five-and-a-half years, with a non-parole period of three years and eight months.

The judge said Ikhtiari was a man of courage and honour who had spent four years apart from his family as he sought refugee status before they were reunited in New Zealand.