Prime Minister John Key has confirmed that Victoria Cross winner Corporal Willie Apiata is back in Afghanistan and says it is unlikely he will return to New Zealand.

Mr Key's comments came after a photo of two unidentified SAS soldiers in Kabul was published by the Herald, and other media today.

After condemning the Herald for running the photograph Mr Key identified one of the soldiers as Corporal Apiata.

He said Apiata chose to stay on in the SAS, despite the wall to wall coverage of him being awarded the Victoria Cross.

He said no decision had been made on whether Apiata or the other soldier pictured would now leave Afghanistan and said it was known when the SAS returned that they would be more high profile and were likely to be photographed.

"I think it's unlikely that Willie Apiata would return to New Zealand before the end of this rotation. At the end of the day, people knew he was in the SAS and there was always the chance people might take the view that he might be back there," Mr Key said.

Mr Key was concerned for the safety and the lives of New Zealand's elite soldiers.

"Certainly if he wanted to come home now, we would allow him to. He's probably the most high profile New Zealand member of the SAS and his face has been plastered across the world's media.

"When we sent the SAS back to Kabul, it was always going to be a much more high profile deployment. On that basis, they were much more likely to be seen and to be photographed. We were aware of that when we made that decision but we were comfortable with it.

"A high level of secrecy around the SAS is needed. The Taleban and Al Qaeda were always aware they were there so there was no secret that the New Zealand SAS were in Kabul. But we don't want them to know the names and individual identities of members of the SAS because of the nature of some of their operations, and they would be at a greater risk if they can be identified," Mr Key added.

"He was well aware of that before he made the decision to go back and he was pretty much the first to put up his hand to go back."

Mr Key said Apiata was not in any more danger than anyone else.

Mr Key said he was "disappointed" the picture had been published.

"I'm very disappointed at the New Zealand Herald's decision to publish the photograph on the New Zealand SAS soldiers without blacking out the face of the particular soldiers.

"It puts at risk the lives of those individual soldiers because they can now be recognised and I think that was a poor editorial decision by the New Zealand Herald," Mr Key said.

He said the use of the photo was "not helpful to him".

The photograph is the first picture of the New Zealand Special Air Service troops in the Afghanistan capital, Kabul.

The NZ Herald's assistant editor John Roughan said it published the photo for its news value and never intended naming Apiata.

"It was New Zealand's first glimpse of our forces in Kabul," he said.

"We didn't even know they few were there until a days beforehand, when the New York Times revealed it to us...this was the first chance we had to actually look at them, to see them in action."

Mr Roughan didn't believe the photo put the men at extra risk.

"That's something that we always consider, but in this case the soldiers were out in a public place, in a public street, in a major city, visible to anybody, wearing uniform, carrying their guns...there seemed no reason for the Herald or anybody else to hide their identities."

He said the paper would do the same thing again, "... if we had pictures of news value and we were confident that they wouldn't put anybody at risk."

The troops are thought to have been among the small group of Kiwis who helped in response to Taleban gunmen and suicide bombers who struck the capital on Monday night.

More than a dozen people were killed in the raid.

Their presence at the incident was reported by the New York Times earlier this week. The NZ SAS's presence in Afghanistan was confirmed by Mr Key in October after it was revealed by Norway's defence chief.

Mr Key said today that Apiata, who was the most high-profile member of the SAS, is likely to be aware that the photograph has been published.