Updated 3.47pm: A US Department of Defence report's found major deficiencies in the coalition training base at Taji Air Base in Iraq.

It's the facility the Prime Minister's just returned from visiting - he's observed the efforts of Kiwi troops stationed there in providing training to their Iraqi counterparts.

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According to the report, the Iraqi Army doesn't have proper records of what is stored there, with some equipment having sat idle and unused for up to five years.

It has also found facilities to house Iraqi Army trainees are inadequate, and poor living conditions are having a significant effect on their morale.

The report also says some militias are better equipped than the Iraqi Army, which likely has a detrimental effect on Iraqi Army recruitment and retention.

New Zealand First MP Ron Mark thinks the report shows all is not well at Taji.

Ron Mark describes the report as "no-holds barred" and said it casts a shadow over our Prime Minister's visit to the base this week.

"Essentially the Prime Minister wants to put a good spin on the mission to make it look as good as he possibly can."

"But behind the scenes the Inspector General of the Department of Defence in the United States is saying it's a dog."

He said it's clear Iraqi officers don't "give a stuff about their soldiers".

"That will result in desertions and at the very least AWOLs. (Away without official leave) What it will also lead to is soldiers changing sides and fighting either with the militia or on the other side."