Resources Minister Keith Pitt has made it abundantly clear the Nationals will fight tooth and nail against adopting a target of net zero emissions by 2050.
Prime Minister Scott Morrison has used an overseas trip to lay the groundwork for adopting the climate target later this year.
He said it was very clear the world was moving to net zero emissions and a new energy economy was coming.
But back home, Mr Pitt has signalled the Nationals are not on board.
He said Australia had not committed to the target and doing so would require agreement from the junior coalition partner.
The cabinet minister said agreement had not been sought and the Nationals had not even been asked.
"I think they would be unsupportive but we are yet to have that discussion," Mr Pitt told ABC radio.
"We haven't been asked and there's been no change in our position."
Mr Pitt said adopting a net zero emissions target would "absolutely" cause damage to industries in regional communities and was not government policy.
Michael McCormack was quizzed about his colleague's comments during Question Time on Thursday.
The deputy prime minister refused to say whether Mr Pitt was correct and only offered a vague response.
"Emissions are 20 per cent lower than they were in 2005. We should be proud of that," he told parliament.
"They're lower than what the United States of America, what Canada has produced and I tell you what we'll do as Nationals, as Liberals. We will do it with technology, not taxes.
"That's how we are going to reduce emissions."
The prime minister has repeatedly stated Australia is aiming to get to net zero emissions "as soon as possible and preferably by 2050".
Mr Morrison is confident he can win over the Nationals.
"We're just working the problem, and the problem is how we address a world that is moving to a new energy economy, a new carbon-neutral economy, that is going to happen," he told Sky News.
"This is where the world is heading and that has profound implications for Australia. We have to ready ourselves for that."
At the same time, Mr Pitt is urging oil and gas producers to fight back against environmental and shareholder groups campaigning against the expansion of the fossil fuel industry.
He has declared coal will be around for many years to come.
Australian Associated Press