Rail companies Aurizon and Pacific National have filed notices of cross appeal with the Federal Court as they prepare for hearings on the competition watchdog's attempts to block the $205 million sale of Aurizon's Acacia Ridge freight rail hub.

Justice Beach ruled the Acacia Ridge sale could go ahead after Pacific National agreed to provide undertakings that it would not discriminate against other rail operators who wanted to use the terminal, which acts as a major hub for rail freight moving in and out of Queensland.

The ACCC is understood to argue in its appeal that the judge did not have the powers to accept the undertaking. and that it does not think the undertaking will be effective in protecting potential anti-competitive conduct by Pacific National.

Mr Sims said in May that Pacific National could frustrate potential users of the terminal by deciding when exactly they could use it.

Aurizon and Pacific National disagree with the ACCC.

Pacific National, which plans to run the terminal as a separate business unit, must appoint independent experts to monitor access requests and meet key performance indicators, including targets linked to getting trains ready for departures, truck turnaround time, freight availability and transaction times per container.