The measures in the Reef 2050 plan on ports and dredging take existing strong regulation to perhaps the toughest standards in the world, according to Queensland Resources Council CEO Michael Roche.

“Those measures will inevitably come at an economic cost to Queensland over time,” he said.

“The legislated ban on disposal at sea of material from capital dredging will inevitably mean that some future necessary port developments will not proceed or will have to be scaled back because of a lack of land-based disposal or reclamation options and/or because of cost.

“All those in government and industry who have worked so hard to develop the Reef 2050 Plan cannot rest on their laurels.”

The draft recommendation on the GBR issued in Paris is based on facts and science and has not been diverted by claims by activist organisations that the GBR should be placed on the “in danger” list of world heritage properties, according to Roche.

“Any such decision would have been a travesty in light of the undisputed recognition that the GBR is the best managed reef system in the world and the fact that Australia’s excellent management of the reef has been lifted to an even higher level through the Reef 2050 long-term sustainability plan,” he said.

“The deceitful campaigns of the activists will inevitably become more strident and shriller in the weeks leading up to the meeting of the World Heritage Committee in Bonn.”

Federal Environment Minister Greg Hunt flew to the Whitsundays on Saturday afternoon to visit the reef, hours after UNESCO released its draft ruling on the icon's status.

“I'm going to snorkel this reef this afternoon just to have a moment to myself to recognise that whatever we do nature does it better,” he said.

“At the end of the day, this is the strongest possible endorsement of what Australia and Queensland are doing.

“It is not, as some would have it, a probation – all references to 'in-danger' have been removed.”

Queensland Environment Minister Steven Miles was confident the Reef 2050 plan would yield results.

“We will start to see a turnaround in coral cover and a turnaround in the quality of reef,” he said.

The preliminary ruling requires Australia to give a progress report on its commitments by December 1, 2016.