Australian employers and unions are at odds over a proposal by companies to change workplace flexibility and pay. Among the changes eyed are cutting minimum working hours and pay.

The proposal would reduce to 90 minutes a day minimum working hours for school students and weekend pay for casuals. The employers also want to do away with evening penalty rates and craft a narrower definition of shift work.

The unions, which analysed over 2000 applications filed with Fair Work Australia (FWA), said the companies are setting the tone for a government led by Opposition leader Tony Abbott that would reduce wages and worsen workplace conditions.

"What employer groups want is a 24-hour, seven-day-a-week economy in which they have all the flexibility, the power and control over who works when and how little they are paid," Australian Confederation of Trade Unions Secretary Jeff Lawrence was quoted by The Sydney Morning Herald.

However, the employers blamed the Australian Labor Party while under Kevin Rudd and Julia Gillard for the cut to entitlements for some workers which they said was a result of allowing costs to go up for enterprises.

FWA will study the future awards which cover most jobs in Australia. The agency accepted submissions from employers, unions and other stakeholders until March.

Other changes sought by employers include lower rates for apprentices and trainees in lieu of adult pay rates, redefinition of shift work to cut access to pay and leave entitlements, and new annualised arrangements to avoid payment of allowances, penalties and overtime.

"Australia's employer groups have never accepted the reality that Work Choices-style laws were wholeheartedly rejected," Mr Lawrence pointed out.

"The ACTU is implying employers are being greedy and unreasonable in these demands, but is failing to disclose the areas where employers have had to accept significant new regulations and costs," Australian Chamber of Commerce and Industry Chief Executive Peter Anderson countered.

Australian Industry Group Director of Workplace Relations Stephen Smith cited afternoon shift loadings in the glass industry which hiked rates to 50 per cent from 15 per cent and caused a major dent to costs in the industry.