Former Defence Minister Wayne Mapp has conceded that civilians were killed in the 2010 Afghanistan raid that is the focus of Nicky Hager and Jon Stephenson's new book.
The book claims Dr Mapp told a friend the operation was New Zealand's "biggest and most disastrous operation - a fiasco".
When Newshub's Mitchell Alexander asked about the quote in the book on Wednesday, Dr Mapp did not back away.
Newshub: "Did you say the 2010 raids were one of most disastrous operations - do you stand by those comments?"
Mapp: "At the time the raid took place the soldiers thought they were engaging with insurgents, that's how people were acting, that's what the report was at the time."
Dr Mapp was asked about the quote a second time.
Newshub: "Did you say the 2010 raid was one of the biggest and worst operations that have taken place?"
Dr Mapp: "We didn't achieve the objective we sought, which was the capture of a named group of people."
Dr Mapp denied civilians were killed when the raid became public in 2011, but was open about it on Wednesday.
"One of the disasters of war is these terrible things can happen," he said.
When asked if he was remorseful, he replied: "In 2014 I was informed that, I saw it on TV in fact, that a three-year-old was killed, I'm sure everyone is remorseful about that. At the time of the attack they thought they were being attacked by insurgents."
Dr Mapp was the Defence Minister on the ground in Afghanistan when the "Hit and Run" raid took place in 2010.
Hit and Run: The New Zealand SAS in Afghanistan and the meaning of honour, released on Tuesday by Mr Hager and Mr Stephenson, alleges the SAS led an operation which led to the death of six civilians and injured 15 more during a raid on two isolated villages in Tirgiran Valley, Baghlan, Afghanistan on August 22 2010.
The book's authors claim the Tirgiran raid was a retaliation against the killing of 26-year-old soldier Tim O'Donnell on August 3.
Dr Mapp resigned from Parliament in 2011 and until now has never spoken publicly about what happened in Afghanistan, but according to the book he confided to a friend that the Defence Force was " doing too much I didn't know about".
On Wednesday Dr Mapp said the operation did not achieve its objectives. But although he won't back away from the "fiasco" comments, he still backs the soldiers.
"This was at night, limited visibility, they thought they were being attacked. They did what a professional soldier would be expected to do which was is defend themselves."
"They were in an area of known hostility. Around that area, the New Zealand cartel was being attacked by rifles, by machines, by rockets and so forth and it seemed to emanating from that general area."
He says former Prime Minister John Key, who the book alleges signed off the raid, should not be worried, "because he acted on proper advice".
"He, like myself, like Jerry Mateparae, act on the advice that we get. The soldiers involved act in accordance with the threat they are dealing with."
Hit and Run claims then-chief of Defence Force Lieutenant-General Jerry Mateparae watched the operation from an SAS operations room in Kabul.
Sir Mateparae told Newshub on Wednesday: "If you want to talk about the just released Nicky Hager - Jon Stephenson book then I will decline.
"As far as I can see, all that needs to be said has been said and anything further should be addressed by people in New Zealand who have access to the relevant information."
Dr Mapp is not laying blame on anyone's shoulders, saying 'blame' was "not really the right word".
"People acted with honest intent, and acted in the circumstances what they thought was right."