A politics academic says Prime Minister John Key broke his promise to the New Zealand public that the Special Air Service (SAS) personnel in Afghanistan would not be fighting alongside the soldiers it was training.
Green Party MP Keith Locke says the Government's credibility is now on the line.
SAS unit member and Victoria Cross hero Willie Apiata was photographed in the Afghanistan capital of Kabul last week, moments after he came out of a building where three bodies were found.
Photographs of Corporal Apiata and another SAS soldier taken by French freelance photographer Philip Poupin were published by several New Zealand media outlets.
Poupin said the men were there to fight and he personally saw three dead bodies in the building they came out of.
Prime Minister John Key previously said the SAS had a "very limited" role in the battle and fired no shots.
Defence Minister Wayne Mapp also said that the SAS members were not as close to the fighting as Poupin suggested.
However the Sunday Star Times today reported that news reports showed the SAS and Afghan commandos were involved in combat with the Taliban fighters.
Otago University international relations specialist and a former Afghanistan cabinet minister Najib Lafraie said "the only plausible explanation" was that "John Key went against the pledge he has made to the New Zealand public".
Mr Key last year said the SAS would not fight alongside the Afghans they would be training because it was "particularly dangerous". The SAS are now training an elite group of Afghan commandos known as the Crisis Response Unit (CRU), also known as Task Force 24.
Mr Locke, in a statement this afternoon, said the Government had a credibility problem over the SAS deployment.
"Corporal Willie Apiata and his colleague, in the picture published last week, did appear to be on a joint mission with Afghan commandos responding to a Taliban attack in Kabul's Pashtunistan Square. Foreign journalists have confirmed the SAS were involved in some way.
"I will be asking questions of government about this when Parliament resumes in February. We have been given far too little information about what the SAS is doing in our name in Afghanistan, and not all the information we are given appears to be accurate.
"Whatever the rights and wrongs of Corporal Apiata's photo being published in the New Zealand media, our Defence Force can't escape some responsibility for putting Corporal Apiata at risk. They sent him back to Afghanistan, knowing his picture was everywhere. Even now the NZDF website carries a photo of a bearded Willie Apiata, apparently in the field."
Mr Key did not comment to the newspaper and NZPA's request for comment was not responded to. Dr Mapp told the newspaper the CRU played only a back-up role in the fighting.
"The actions that took place were essentially the domain of the Afghan national army, which, you can see from the photos, were the people actually engaged in the fighting."
The CRU was not directly involved in the action, he said, and neither were the SAS.
Norwegian defence correspondent and author of a book on the Norwegian special forces Tom Bakkeli disagreed. He said the CRU "absolutely were involved in the fighting" and "the CRU got a lot of acclaim for their counter-action against the attacking Taliban and suicide bombers".
The SAS took over the training of the counterterrorism CRU from the Norwegian special forces after they left Afghanistan in September.
Dr Lafraie believed New Zealand's stance had changed under pressure from the US.
Dr Mapp told the newspaper it was taking Mr Key's statement out of context. There was no contradiction between the news reports of the battle and the Government's position.
"A lot of people were involved, it took place over many hours and there was confusion." Dr Mapp said he did not want a detailed discussion of what happened.
NZPA