The competition watchdog will allow six coal miners, including Rio Tinto, to collectively bargain with QR National for access to its rail network linking Queensland’s Bowen Basin to the Abbott Point port.

The miners had sought authorisation for collective bargaining from the Australian Competition and Consumer Commission, arguing it would significantly lower the cost of exporting coal.

The miners are Carabella Resources, Macarthur Coal, Middlemount Coal, New Hope Corporation, Peabody Energy Australia and Rio Tinto Coal Australia.

“The ACCC considers that these arrangements will result in significant transaction cost savings and help to avoid potential delays in the terminals’ construction and new coal export earnings,” ACCC chairman Rod Sims said in a statement on Thursday.

“The ACCC is satisfied that the voluntary nature of the arrangements, the limited composition of the collective bargaining group and the limited scope of the negotiations will mean that any potential detriment is minimal.”

The authorisation provides statutory court protection from action for conduct that might otherwise raise concerns under the Competition and Consumer Act.

The collective bargaining authorisation is proposed to last for 15 years, to allow for the development of the North Queensland Coal Terminal and Rio Tinto Terminal, the ACCC said.