Prime Minister John Key is certain that claims by the Guardian News Paper are false in respects to New Zealand defence personal serving combat roles in Iraq.

Iraqi Kurdistan officers claim New Zealand special forces are operating on the frontlines in Iraq.

On Friday, Defence Minister Gerry Brownlee denied claims in international media that New Zealand special forces are calling in airstrikes in northern Iraq, "or involved in any other combat operations" in the country.

However, an ex-US intelligence advisor, now based in New Zealand, says New Zealand SAS in Iraq should come as no surprise.

CHARLOTTE CURD/FAIRFAX NZ The Guardian is reporting: "British, Australian and New Zealand SAS are all active in northern Iraq, along with US forces."

The Guardian reported: "British, Australian and New Zealand SAS are all active in northern Iraq, along with US forces, where they have been calling in airstrikes to support both Kurdish and Iraqi advances. Their role at the front line has not been well documented, however."

READ MORE: Prime Minister John Key rules out SAS troops in Iraq

A Guardian News & Media spokesperson said the ​claim that the New Zealand SAS was present in northern Iraq was based on ​accounts from peshmerga officers.

Peshmerga are the military forces of the autonomous region of Iraqi Kurdistan.

Following the publication of the story, Brownlee's spokesman released a statement saying: "I am not going to discuss operational details, however it is incorrect to say we have SAS calling in air strikes, or involved in any other combat operations in Iraq.

"As the Prime Minister has said publicly the Government has ruled out sending SAS, or any troops into combat roles in Iraq.

"We have also been clear that special forces could be deployed for short periods – for example, to provide advice on issues like force protection or to help with high profile visits, as they have many time before."

Stuff has sought further clarification from Brownlee's office.

The Guardian has since updated its online article to reflect the claims came from peshmerga officers and have included Brownlee's statement.

NZSAS IN IRAQ 'NO SURPRISE'

Former US intelligence advisor and security expert Paul Buchanan said it seemed obvious that New Zealand special forces would be deployed in Iraq.

"Notwithstanding the New Zealand Government's semantic gymnastics, reports of NZSAS involvement in the fight to liberate Mosul are not surprising and to be expected."

They were an "elite force" whose corresponding units from Australia, the UK, Canada, the US, as well as other coalition members were all involved in the fight against Islamic State, Buchanan said.

Kiwi special forces trained and deployed with these units from other countries on a regular basis.

"A country does not maintain such a force without the intention to use them in conflict zones, and as a member of the anti-Daesh coalition New Zealand is no different in this regard."

Although the Minister of Defence speaks of "advisory roles", "advice" in this context involved embedded, direct and close on-the-ground support for Iraqi and/or Kurdish forces, much in the way the NZSAS conducted operations as counter-terorism advisors in Afghanistan, he said.

"The NZSAS may not be forward-based in Iraq, but it should come as no surprise that they are deployed there."

In the past, Buchanan has said he had received "credible reports" that New Zealand SAS was carrying out missions in Iraq. These troops may not be based in Iraq but were likely based nearby in a place such as Djibouti and deployed to Iraq to carry out tasks.

SAS INVOLVEMENT COUNTER TO MISSION

In February, Prime Minister John Key said using the SAS ran counter to New Zealand's current mission in Iraq, which was focused on equipping Iraqi soldiers to take the fight to Islamic State (Isis) themselves.

There are personnel based at Camp Taji, North of Baghdad, where they train Iraqi military forces.

United States defence secretary Ash Carter issued a global call for extra help last December, including elite troops, air strikes, and the provision of ammunition and training.

But Key, in February, indicated the SAS was off the table.

"I think we can pretty much categorically rule out special forces at this time in terms of that Ash Carter letter that we received.

"We don't see that fitting in with what we are doing," Key said.