Updated 1.36PM: There are suggestion our government has already made a commitment behind closed doors to send troops to Iraq.

A report in The Australian over the weekend hints that a deal is already done between New Zealand and Australia, which would see us sending 100 troops, and Australia 300.

Defence Minister Gerry Brownlee is refusing to comment on the report.

The Government's also being urged to be upfront about the real risk of sending Kiwi training troops to Iraq.

Cabinet's due to make a decision on the controversial proposal today.

The Prime Minister says New Zealand should put troops at risk now, rather than risk losing the lives of more New Zealanders in future.

"We really, I don't think, have the option of doing nothing. The question becomes what do we do because 60 countries are doing something, and for every country that something looks a bit different."

John Key says while any potential contingent wouldn't be fighting, we have to accept they are going into a high risk environment.

"I think the way of looking at that is do we run the risk of losing lives of New Zealanders on the basis of ISIS becoming stronger, and I believe the answer to that is yes."

The Prime Minister says whatever decision is made today will likely be announced tomorrow.

Labour Leader Andrew Little says the Government needs to be open and upfront about the level of risk our troops will be facing.

"If the government is going to take that risk in our name, and somebody is killed as a result, then people will know that is the risk the government is prepared to take. It's important also to be clear that the Iraqi government is saying military assistance isn't the only thing, it isn't even their top priority."

He says if Cabinet makes a decision, he'd have thought the public should be told straight away.

Labour defence spokesman Phil Goff says it's clearly already been decided, and the Prime Minister is being dishonest.

He says John Key is only denying it in New Zealand, and is closing down debate in Parliament on whether it's the right course of action.

The fact Parliament will have no say over troops being sent to Iraq is sitting poorly with the Greens, with MP Kennedy Graham saying it's not democratic.

New Zealand First Leader Winston Peters says we shouldn't go and predicts any deployment will have a tragic outcome.

He argues we're not working under the legal umbrella of the United Nations, just on a request of one of the factions that has a grudge against the others.

Peters believes democratic debate is being ignored.

"Government's don't go to war, countries do," he said

"People are all caught up with it, and that being the case it's democratic body, namely parliament, should be making the decision."