Hundreds of thousands of workers would lose a significant portion of their pay this long weekend if the Abbott Government and employer groups had their way.
ACTU Secretary Dave Oliver said workers such as nurses, hospitality and retail staff would have upwards of $200 ripped from their wages for working on Monday, which is a public holiday in most states.
"We are in the midst of a united attack on the pay packets of hardworking Australians. If the Abbott Government and bosses had succeeded so far, this long weekend, workers would miss out on compensatory pay," Mr Oliver said.
"As many Australians look forward to a long weekend spent with friends and family, others will be working to keep them safe, serve them when they go out, nurse them and race to their aid if they need assistance.
"Nurses, police, ambos, firefighters, retail and hospitality workers are just some of those working on Monday. The Abbott Government and employers want to rip money out of the pockets of workers this long weekend and every weekend.
"This has nothing to do with job creation or productivity, it's about attacking people's pay.
"For essential services, public holidays and weekends are often very busy and difficult shifts. And on top of that they miss out on catching up with loved ones.
"Most Australians understand that the person serving them at a shop or cafe while they enjoy the weekend deserves to be paid extra."
Mr Oliver said in a sign of how determined the Government and business are to lower people's wages this was a two-pronged attack.
"As well as launching a war on penalty rates, you have employers and the Abbott Government lobbying against a rise in the minimum wage using arguments which, quick frankly, call into question their economic credibility."
Mr Oliver said there was no evidence linking productivity or employment levels with penalty rates or modest increases in the minimum wage with an impact on job creation.
"Employers have been trying to go after penalty rates for years despite never having any evidence to back up their claims about productivity," he said. "Now, with the green light from the Abbott Government employers are once again launching the same old arguments.
"Just this week you had Western Australian Senator Dean Smith parroting the same unsubstantiated arguments that employers make in a newspaper opinion piece.
"We will fight this unfair push to cut people's pay in workplaces, we will fight it in the Industrial Tribunal and we will fight it in the community."
Media contact: Kate Bell 0414 873 625