The Greens have accused NSW Premier Barry O'Farrell of "rolling out the red carpet" to James Packer following reports he's refused to release a report on the businessman's casino bid.

An independent report on key aspects of the $1 billion resort hotel at Barangaroo was completed last year, but Mr O'Farrell has refused to release it, Fairfax reports.

Greens MP John Kaye said the decision to "hide the report" raised yet more questions about the project and its approval process.

"So far the one casino limit has been dumped, the unsolicited proposal process has been weakened and Crown has been given control over the media messaging about the assessment.

"Now a document that might be critical of the bid has been hidden from the public," he said.

"The community is being denied access to crucial information about the proposal."

Mr Packer's Crown Limited has claimed the proposed six-star hotel would not be financially viable without the revenue from a VIP-only casino, which it has said will not contain poker machines.

The report includes whether a casino is necessary for the project's financial viability, Fairfax said.

"The document is central to the unsolicited approval process but it is being kept under wraps," Mr Kaye said in a statement.

"The premier is rolling out the red carpet to James Packer."