The NSW auditor-general has reprimanded the charity running Sydney's Catholic cemeteries after it refused to open its books for audit.

The Catholic Metropolitan Cemeteries Trust (CMCT), which operates cemeteries such as Rookwood in Western Sydney, has been at loggerheads with the former Coalition government over attempts to hand control of burial grounds to a state-run body.

The group was referred to the auditor-general in 2021 by the former government after Greens MLC David Shoebridge raised concerns it was misusing funds.

Auditor-General Margaret Crawford has released a 'special report' which is only a few pages long, citing several refusals by the CMCT to comply with her requests.

She said the situation was unprecedented.

"Being denied access to management, and to proper books and records for the purposes of conducting statutorily required financial and performance audits should not be normalised, nor considered appropriate," she wrote.

"It significantly impairs transparency and accountability and raises questions about the stewardship of resources."

A timeline of correspondence said the audit office had contacted the charity nine times since September last year, asking to see relevant documents.

Ms Crawford's brief report recommends the NSW Treasury look at options to enforce the CMCT's reporting obligations.

The CMCT has been contacted for a response.

The CMCT threatened legal action when the previous Coalition government proposed putting all cemeteries under the control of government body OneCrown, to standardise pricing for burial plots.

At the time, the Catholic trust called the move an "attack on religion".

The proposal also angered Muslim and Jewish groups.

Labor's Lands and Property Minister Steve Kamper has since proposed a two-model system, which would allow the Catholic group to retain control of some cemeteries while the rest come under OneCrown.

In a statement, a spokesman for Mr Kamper said the issue had been dragging on.

"This matter was raised with the former government and for 14 months they failed to act," the statement said.

"I am considering the issues that the auditor-general has raised and the options available to the government to address this matter."

The CMCT is a registered charity and reports publicly to the Australian Charities and Not-For-Profits Commission.