Maurice Newman, chairman of the Prime Minister's Business Advisory Council, said the real agenda was "concentrated political authority. Global warming is the hook".
In a column for The Australian newspaper to coincide with a visit by UN climate chief Christiana Figueres, he added that the world had been "subjected to extravagance from climate catastrophists for close to 50 years".
"It's a well-kept secret, but 95 per cent of the climate models we are told prove the link between human CO2 emissions and catastrophic global warming have been found, after nearly two decades of temperature stasis, to be in error," he said, without providing evidence.
"Figueres is on record saying democracy is a poor political system for fighting global warming. Communist China, she says, is the best model," he wrote.
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"This is not about facts or logic. It's about a new world order under the control of the UN. It is opposed to capitalism and freedom and has made environmental catastrophism a household topic to achieve its objective."
Figueres, in charge of getting a global emissions reduction agreement in Paris in December, was in Australia to discuss practical climate change action.
In an interview with the ABC this week, Figueres said the nation had no option other than to gradually step back from coal -- a key economic driver.
Newman said "hopefully, like India's Prime Minister Narendra Modi, Tony Abbott isn't listening (to the UN)".
But he warned that "having gained so much ground, eco-catastrophists won't let up".
"After all, they have captured the UN and are extremely well-funded. They have a hugely powerful ally in the White House," he said.
"And they will keep mobilising public opinion using fear and appeals to morality.