Sending New Zealand special forces to Iraq at the request of the US has been "pretty much categorically ruled out", the Prime Minister says.
The Government received a generic letter from US Defence Secretary Ash Carter in December asking for help, including elite troops, air strikes, provision of ammunition and training.
But in his post-Cabinet news conference today, John Key said New Zealand wouldn't be taking up the request.
"I think we can pretty much categorically rule out special forces at this time, in terms of that Ash Carter letter we received."
New Zealand currently has around 140 soldiers at Camp Taji in a joint operation with Australia, training their Iraqi counterparts.
Mr Key says sending the special forces into Iraq wouldn't fit with what New Zealand's mission was.
"We don't see that fitting with what we're doing, but that's always subject to future request. But in terms of that particular request our view of that is that we don't want to do something there."
And it's not what the Iraqi government wants either, he says.
"I'm not sure what the Americans would want [New Zealand soldiers] to do. But the Iraqi government and Prime Minister [Haider] al-Abadi was quite clear with me that's not what they want. They want their troops trained and they want to fight their own battles."
A planned government review of the progress of Kiwi troops in Iraq is about to get underway, and Mr Key says it's so far been fruitful.
"Our starting position is that it has been very successful and there has been real progress made. We're obviously training forces; they're doing well. They were part of the effort to retake Ramadi.
"The Iraqi government has regained about 40 percent of the territory it had lost to Islamic State. I think in all accounts it's been a very successful mission."
The mission will be part of talks Mr Key has with Australian Prime Minister Malcolm Turnbull when he travels to Australia on Friday for the annual leaders' talks between the two countries.