The Australian Consumer and Competition Commission has appealed to the Federal Court to review the Australian Competition Tribunal's recent decision on the terms of access by Glencore to services at the Port of Newcastle.
It follows the tribunal's rearbitration of an access dispute between Glencore and the Port of Newcastle in October about the charge for ships entering the port to export Glencore's coal.
Glencore is the biggest exporter of coal from Newcastle, and the navigation service charges are the port's main source of revenue.
The tribunal ruling, which did not apply to other coal companies using the shipping channel, was due to expire in 2031.
"While the Tribunal took the same approach as the ACCC on a number of issues, the ACCC is seeking review of the Tribunal's treatment of user funding at the port," ACCC Chair Rod Sims said on Thursday.
A significant part of the dispute is about whether the costs that the Port of Newcastle is allowed to recover should include the costs for dredging the shipping channel that were historically funded by various users of the port.
The ACCC excluded these user funded amounts in its original arbitration and determined an access charge of $0.61 per gross tonne as at 1 January 2018. However, the tribunal included these amounts and determined an access charge $1.01 per gross tonne.
The tribunal's decision allows the Port of Newcastle to recover the user funded amounts in its access charge.
"The ACCC does not consider it to be economically efficient for a service provider to be allowed to charge any user for costs of assets that have already been funded by users," Mr Sims said.
"Our appeal will focus on what we will argue are errors in the way the Tribunal has approached the principles of user funding, which could have implications for other regulatory matters."
Mr Sims previously argued that allowing the port to become an unconstrained monopoly was not in the economy's best interests.
Port of Newcastle chief executive Craig Carmody said on Thursday said the ACCC appeal was a disappointing development.
"Port pricing should remain subject to an appropriate and efficient commercial relationship between the port and its customers," Mr Carmody said.
"The endless legal battles erode confidence in investing in infrastructure, be it at the mine or at the port, in one of Australia's most important export industries.
"We will continue to sit down with our customers to discuss our services and pricing, respecting the need for all parties to return to a normal commercial relationship."