New Zealand will send troops to Iraq on a 'behind-the-wire" non-combat mission to boost the local military's ability to fight the Islamic State (IS) group, Prime Minister John Key said Tuesday.
Key said about 140 troops would begin the mission in May after a request from the Iraqi government for international help to increase its military capability against the jihadists.
"We cannot, and should not, fight Iraq's battles for them -- and actually Iraq doesn't want us to," he told parliament.
"Our military can, however, play a part in building the capability and capacity of the Iraqi forces so they can fight ISIL themselves."
Key flagged the mission late last year and it has been hotly debated in New Zealand, with all major opposition parties against it.
A TVNZ opinion poll released this week found 48 percent of participants supported a military training mission, with 42 percent against and the rest undecided.
Key said New Zealand was part of a 62-nation coalition against the Islamic State organisation, also known as ISIL or ISIS, which has captured swathes of territory across Iraq and Syria.
He described the group -- infamous for beheading, stoning and burning alive its victims -- as "barbaric", saying New Zealand would "stand up for what's right".
"Sending our forces to Iraq is not an easy decision but it is the right decision," he said.
He added that New Zealand troops would most likely work alongside their Australian counterparts at a military base in Taji, north of Baghdad.
Key said the initial deployment was for nine months and the mission would not extend beyond two years.
The leader of the main opposition Labor Party, Andrew Little, said New Zealand should concentrate on supplying humanitarian aid to Iraq, rather than conducting military training.
"We won't fix the (Iraqi) army, it is disorganised, it is broken, it is treacherous and it is corrupt," he told parliament.
Green Party leader Russel Norman criticised Key for refusing to put the planned mission to a parliamentary vote, saying he knew he would lose.
"Democracy, it seems, is a military export and is not for domestic consumption," Norman said.
In a fierce parliamentary debate, Key said opposition leaders should "get some guts and join the right side".
"I will not stand by while Jordanian pilots are burnt to death, while kids execute soldiers," he said. "This is the time to stand up and be counted."
New Zealand, part of the so-called "five eyes" intelligence network involving the United States, Britain, Australia and Canada, has faced pressure from allies to join the anti-IS effort.
British Foreign Secretary Philip Hammond urged the country to make its military expertise available when he visited Auckland this month.
"Frankly we've got used to New Zealand being there alongside us, alongside the US, the UK, Australia, as part of the family," Hammond said.
Key said in January that New Zealand was expected to assist the military effort, adding "there has to be some contribution, it's the price of the club".
New Zealand did not participate in the US-led invasion of Iraq to oust Saddam Hussein in 2003, although it sent two 60-odd strong contingents of engineers to Basra in 2003-04 after a UN request for help in reconstruction efforts.
The country also sent a reconstruction team and small special forces contingent to join the NATO-led operation in Afghanistan in 2003, resulting in 10 New Zealand deaths during the decade-long deployment.