Prime Minister John Key says he is happy to take the flak for a decision to extend New Zealand's military involvement in Iraq for an extra 18 months.
On Monday, Cabinet agreed to leave defence force personnel in Iraq until November 2018. They were due to return home in May 2017.
Opposition parties said it was a broken promise because the government had said it was only committing to a two-year mission.
New Zealand troops have been part of a joint mission with Australia, based in Camp Taji, just out of Baghdad, since May last year.
They've been training members of the Iraqi Security Force as part of international efforts in the fight against Islamic State (IS).
When Mr Key visited Taji camp last year, he said the deployment had been given a specific deadline of two years, and he had no intention to extend it out any further.
Green Party co-leader James Shaw said extending that term was another broken promise. He said troops should have pulled from Iraq.
"It would be much better for New Zealand to play a humanitarian role.
"New Zealanders lives are at risk and it does increase the threat to New Zealand's security to be engaged militarily."
New Zealand First leader Winston Peters said it was never going to be just a two-year mission. He accused the prime minister of making up foreign and defence policy on the golf course of the United States.
"He's not coming clean to the New Zealand people, this was always his intention.
"I'm certain that was the reason I was asked to go to Iraq as part of a Parliamentary delegation and I believed at the time that there was something unusual about that and I could add no personal value to going and this just confirms it."
Labour leader Andrew Little said last year the prime minister was emphatic the troops would only be there for two years.
"I don't believe he has made the case for why we are still training the Iraqi army which from my observation when I was up there earlier this year poorly led, and not good quality, and I don't think it's a good use of the resources of our soldiers," Mr Little said.
"There's no question good progress is being made and we're seeing it in Fallujah at the moment and there's an assault due on Mosul at the end of the year.
"The bulk of the work that's actually achieving those gains is being done by an outfit called the Counter-Terrorism Service which is nothing to do with the Iraqi army, it's a separate Iraq Government force - we don't have any involvement with that at all."
He said Shia militias, also voluntary forces, were making gains agiansy IS.
"We don't have anything to do with them either - in fact we're explicitly told to keep away from them and the others are the Kurds in the north who have an organised army as well - they're the ones that are making the real gains.
Mr Key admitted he had changed his mind on the deployment but said it was his duty to assess the situation and decide what would be best.
"It's not as quite as simple as being hard and fast, that was what our intention a couple of years ago.
"Of course we could of run this out longer and could of stopped but then we would have had to reconsider, pretty soon I think, what other contribution we'd make," Mr Key said.
After the Paris attacks, the US secretary defence Ash Carter requested more support from coalition partners.
Mr Key said that was part of his decision to extend the mission.
"What we have done is taken a step back and say is this the right time for us to have no engagement in the attempt to defeat ISIL and I think the conclusion we've drawn is no."
He said could not rule out a further extension beyond November 2018 - but he said he was not keen for troops to be there "forever".