Big mining companies have warned the Queensland government not to proceed with the proposed sale of Gladstone port.

The Costello audit of Queensland's finances has recommended selling electricity and port assets, including the Port of Gladstone, to pay down the state's debt.

The government says no decision has been made so far and asset sales won't proceed without an election mandate.

The peak mining lobby group, the Queensland Resources Council, has said it does not want a repeat of the Labor government's sale of Dalyrmple Bay coal terminal to Babcock & Brown in 2002.

Queensland Resources Council chief executive Michael Roche has told the Australian Financial Review that miners expect to be closely consulted on any sale.

"Our experience with privatised ports has not been a good one, Mr Roche told the paper.

"Historically, our industry has not been happy about the Beattie government's sale of Dalyrmple Bay and the subsequent regulation of the port. It has struggled to meet its capacity.

"It was supposed to be 85 million tonnes (a year) but it doesn't do that."

The Dalrymple Bay sale delayed port expansions, and resulted in queues of 30 or 40 coal ships waiting off the coast of Mackay during the mid-2000s, the paper said.

Other coal operators have privately expressed their concerns about the sale of the Port of Gladstone, the paper said.

That's despite industry funding the expansion of Wiggins Island coal terminal at Gladstone and the successful sale of Abbot Point coal terminal in 2011.