Peter Dutton will accuse ­Anthony Albanese of driving-up the costs of new family cars ahead of the March 2 Dunkley by-election and attack the government for refusing to release “secret” modelling underpinning Labor’s fuel efficiency standards plan.

After Energy Minister Chris Bowen made multiple claims on Monday that the British version of the Mazda CX-30 was “25 per cent more fuel efficient than the model available here in Australia”, he backtracked on Thursday to say it was “around 20 per cent”.

Publicly available information says the most fuel-­efficient UK Mazda CX-30 is only 11 per cent more efficient.

In question time, Mr Bowen conceded the “Mazda CX-30, available in the United Kingdom, uses around 20 per cent less fuel than the most efficient Australian equivalent”.

“There are several Mazdas and other models that are more efficient overseas than they are in Australia. And we believe Australians have a right to access those better, cheaper-to-run cars. They can stand for better cars or they can stand against it. That is a choice that is available,” he said.

Mr Bowen did not directly address Coalition claims that the more fuel-efficient Mazda CX-30 cars sold in Britain cost $19,000 more than current Australian models.

Transport Minister Catherine King this week said Australian motorists would face no higher car prices as a result of the government’s preferred fuel efficiency standards model.

Ms King on Thursday refused to release $750,000 ACIL Allen modelling, ignoring a noon deadline set out in a Senate order for the production of documents motion backed by the Coalition, Greens and crossbenchers.

In correspondence from Ms King to Assistant Transport Minister Carol Brown, the former claimed the government’s “impact analysis” was available in its 80-page New Vehicle ­Efficiency Standard consultation paper.

Opposition transport spokeswoman Bridget McKenzie said “there needs to be scrutiny of government claims of alleged fuel cost savings, impacts on new car prices and the availability of the cars Australians love to drive under the government’s (plan)”.

Senator McKenzie said the Coalition was “committed to a low emission transport sector as we head to 2050”.

“Hiding the modelling and pretending there are no losers from Labor’s proposed emission scheme will not wash with the Australian public,” she said.

“This is what Labor did with the disastrous voice referendum, refusing to release the details and just relying on the vibe.

“These modelling reports are sitting on the desks of departmental officials and should be made public.”

Asked by the Opposition Leader whether he believed Australians could afford “a $19,000 increase in the cost of an average family car”, the Prime Minister said Mr Dutton was “completely wrong”.

“He (Mr Dutton) asks stupid questions like that based upon absolutely nothing,” Mr Albanese said.

“This policy says that Australia will have the same standards as the United States has by 2028.

“Apparently now the offer of bipartisanship does not extend to support for the US alliance.

“Everything is an opportunity to try to divide. Having such a thin skin makes it easy to see the glass jaw.”

Mr Dutton and senior Liberal frontbenchers clashed with Mr Albanese in the chamber over the fuel efficiency standards plan, with Coalition spokesman for social services Michael Sukkar booted from question time by the Speaker after having called the Prime Minister a “liar”.

Under the government’s proposed rules, carmakers face fines unless they lower the carbon intensity of their Australian fleets by more than 60 per cent by the end of the decade.

There will be a credit-trading system, with suppliers who beat the targets able to trade credits with those who fall short.

Extracted in full from: