More than 20 items in the National Gallery of Australia's Asian art collection have "insufficient" or "questionable" provenance documentation, a review by former High Court Justice Susan Crennan has found.

Key points: The NGA announced last year it would investigate the ownership history of 54 items in its collection

The NGA announced last year it would investigate the ownership history of 54 items in its collection 14 objects were bought from disgraced New York art dealer Subhash Kapoor

Last year the NGA announced it would investigate the ownership history of 54 items in its collection as part of efforts to review the provenance and legal status of works.

In September 2014, the so-called Dancing Shiva, a 900-year-old bronze statue from the gallery's collection, was returned to India because it was believed to be stolen from a temple.

The NGA bought the statue for $5 million in 2008 from disgraced New York art dealer Subhash Kapoor, who was arrested in 2011 and is awaiting trial in India on charges of conspiracy to commit theft.

Buddha statue returned to India

Former prime minister Tony Abbott returned the Shiva statue to his Indian counterpart, Narendra Modi.

A 2,000-year-old stone statue of Buddha will also be returned to India later this year.

The seated stone Buddha was purchased for the NGA in 2007 by Roslyn Packer, the widow of the late Kerry Packer.

Last year the NGA announced they would receive a refund of more than $1.2 million for the statue.

The NGA maintains it has been a victim of fraud.

Today, the gallery said in a statement the independent review of 36 objects had revealed 22 had "insufficient" or "questionable" documentation, including 14 purchased from Mr Kapoor.

Ms Crennan's audit found 12 objects had satisfactory provenance documentation and two other objects required further research.

Los Angeles-based investigative journalist Jason Felch runs the blog Chasing Aphrodite, which has uncovered instances of stolen art being bought by galleries around the world.

He said when thorough research was done, the claims of provenance often came apart.

"While it's often difficult to find all the answers, what this report underscores is if you ask the right questions and have the right scepticism, you can often indentify those objects that are problematic before you buy them," he said.

Objects to be returned where possible: NGA director

The National Gallery and the High Commission of India have welcomed the report's release.

NGA director Gerard Vaughan said the gallery flagged to the review the sculptures they were most concerned about.

The Seated Buddha statue will be returned to India by the National Gallery of Australia. ( Supplied: National Gallery of Australia )

"So there are no real surprises but what we have now is clarification as to where we stand," he said.

"From our perspective it's a really positive step forward ... because what former justice Crennan has concluded is the processes we put in place to work through every one of the 5,000 items in our Asian collection are good processes."

Dr Vaughan said where objects were found to be clearly stolen they would be returned to the country of origin.

"Other objects, it may be through agreement, because we will never know when they left India or what the circumstances were," he said.

"Other objects we may find that they'll stay here with the approval of the Government of India.

"It's a regrettable situation, but it's a common one."

'They know stuff is stolen'

India's High Commissioner to Australia Navdeep Suri said the review was a step in the right direction.

"To really establish whether an object is stolen you need to have a police report established in India, and it's a pretty complex job to try to match that information with the exact objects that are here," he said.

"I compliment the NGA for the approach it's taken, because frankly there are a number of other countries and institutions, they know that stuff if stolen, but they're not even willing to countenance the restitution to the rightful owners."

Mr Suri said it was important to ensure objects were acquired legally as they were part of India's cultural heritage.

"Sometimes items that have been stolen from a temple or a place of worship also have the additional spiritual significance associated with them," he said.

"Unless other arrangements are worked out they are best located where they came from."