Our troops are committed to going to Iraq, but there are still major details to be worked out before they're deployed in May.

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The announcement up to 143 military personnel are being sent to Iraq in May provoked an uproar in Parliament yesterday.

But there's no deal yet on what legal protection they will have if they need to defend themselves, and injure or even kill someone else.

There's no agreement with Iraq yet on what legal protections our military will have to allow them to do their work - and the proposal to work with Australia is still unofficial.

Chief of Defence Force Lieutenant General Tim Keating says it's now up to Australia to green light a partnership between our defence forces.

"We will partner with another nation, likely to be Australia, and there'll be a task-sharing role where each nation will bring the expertise of that nation to the training curriculum."

Prime Minister John Key says we're unlikely to get the highest protection with a status of forces agreement, but there will be some arrangement.

"Will New Zealand soldiers, when they go overseas, have the legal protection required for them to carry out their duties and functions. The answer to that is yes or they wouldn't be going.

"There are many pathways to achieve that and we're quite confident it will be achieved."

Defence Minister Gerry Brownlee says there's no need to worry.

"We'll negotiate something that we'll give our men and women in the mission the protection they need."

While up to 143 people are being sent, only 16 of them are specialised trainers, despite the aim of the mission being to train local forces.

Brownlee says it's to ensure they're properly prepared and protected.

"They would need other support and we have not been stinting in allowing and to put together a mission that has all those supports in."

Labour, the Green Party, New Zealand First, United Future, and the Maori Party are all opposed to the action, with only Act taking National's side.

Key says Labour leader Andrew Little is just playing politics.

"Because I don't believe him and I know that he is not saying what he would actually do."

Christian groups have also expressed their support for New Zealand troops, entering Iraq in non-combat roles.

The Catholic Church in New Zealand has expressed its support for the move, with Cardinal John Dew saying we can no longer watch ISIS from the sidelines.

And TEAR Fund has made calls for further humanitarian aid, to accompany the deployment of troops.

That's something the Catholic Church also supports.

But both groups are clear they're only talking about non-combat action at this stage.