RAIL unions have accused the Fair Work Commission of launching "a direct attack on workers' rights" after its decision to terminate the enterprise agreements for Aurizon employees.
On Wednesday a full bench of the FWC handed down the decision, which will terminate the agreements on May 18.
The union says this will affect up to 4000 Central Queensland rail workers.
Rail unions, including the ETU, AMWU and AFULE, have vowed to fight for employees' rights and conditions.
AMWU assistant state secretary Terry Bradley said it was an appalling decision.
"This decision has obviously made our members and those of the other unions angry and disappointed," he said.
"They see it as giving a green light to greedy corporates to effectively hold a gun to their workers' heads, hold out for their agenda and when they fail to win the argument simply terminate the agreements and threaten to send workers back to the minimum award conditions."
Aurizon made an application to the FWC to terminate the existing agreements back in May 2014 after failed attempts to negotiate a new agreement with unions.
But an Aurizon spokesperson said they will strive to implement a modern, productive workplace agreement across the business.
Aurizon managing director and CEO Lance Hockridge (pictured) said it was a landmark decision, not only for Aurizon but for Australian industrial relations.
"Our aim always has been to negotiate in good faith workplace agreements that are contemporary and forward-looking, and match those already agreed by unions with our direct competitors," he said.
In handing down their decision the FWC said the provisions "restrict Aurizon in making business changes that it wishes to make in response to a competitive market situation".
"The restrictive provisions restrain Aurizon's capacity to effectively manage its labour resource needs.
"We do not think the changes proposed, objectively viewed, involve exploitation or unfairness in the terms and conditions of employment of Aurizon employees."
ETU state organiser Jason Young said the decision tipped the balance considerably in favour of employers, and the 4000 CQ employees stood to lose considerable conditions.
"We made considerable ground in the last 12 months (of discussion with Aurizon)," he said.
"Hopefully Aurizon won't walk away from all that."
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