Australia launched a probe Wednesday into the agency responsible for protecting the Great Barrier Reef after some board members were urged to resign over alleged conflicts of interest related to the mining industry.

Environment Minister Greg Hunt ordered an investigation after the Australian Broadcasting Corporation aired allegations that coal and gas industry ties had seen the Great Barrier Reef Marine Park Authority (GBRMPA) relax its stance on industrial development.

"I have ordered an immediate independent probity inquiry into the allegations that have been raised," Hunt told reporters.

"The inquirer will report to the chairman of the board at GBRMPA who will in turn report jointly to the secretary of the department and myself."

The authority's chairman Russell Reichelt said Robert Cornall, one-time secretary of the national attorney-general's department, would undertake the review.

GBRMPA is a statutory authority charged with overseeing the protection and use of the reef, and Reichelt said all board positions were filled by government appointment.

He also noted that GBRMPA was required by law "to have a representational board, with members having qualifications or experience related to functions of the authority".

"This reflects the fact that the Marine Park has been a multiple-use area since its inception in 1975," he said.

According to the ABC, two of GBRMPA's five board members have close links to the resources sector -- Tony Mooney, an executive with Guildford Coal and Jon Grayson, who owns a stake in Gasfields Water and Waste Services.

Both men were at a critical meeting last year where the GBRMPA board turned its back on advice from in-house scientists that it oppose port development in areas with "potential to degrade inshore diversity".

Instead, the board issued a watered-down statement saying such biodiversity impact should be a "key consideration" in port approvals, while calling for further consultations with the mining industry on the issue.

Reichelt emphasised that this statement "remains in draft form and will not be finalised until the public has been given an opportunity to comment."

The reef is facing a world heritage downgrade from UNESCO next year due to concerns about rampant coastal development proposed in the region, particularly port, gas and coal operations.

The role of individual board members in the statement on ports is unknown, but conservationists called for Mooney and Grayson to resign in order to address perceptions of a conflict of interest.

"Anyone with coal and gas interests should simply be precluded from serving on the board of management for the Great Barrier Reef," said Senator Larissa Waters from the Greens party.

"It's an international embarrassment that mining interests are allegedly influencing the GBRMPA board, while UNESCO is warning that the Great Barrier Reef could be added to the World Heritage list of sites in danger within a year."

Hunt noted that both Mooney and Grayson "have strong reputations and I don't want to draw any judgement in any direction".

He said he expected Cornall's inquiry would be completed by the end of the year.