Industrial Relations Minister Christian Porter has left the door open to changing the coalition’s workplace law reforms to secure passage through parliament.

The Morrison government will on Wednesday introduce industrial relations legislation designed to cover five key reform areas.

It will address the definition of casual employment, long-term greenfields agreements across the life of major projects, award simplification, compliance and changes to enterprise bargaining.

Mr Porter said the government would not be obstinate about any part of the bill.

“It’s not going to be an all-or-nothing proposal,” he told reporters in Canberra on Friday.

The legislation will be scrutinised by a parliamentary committee before likely being voted on next year.

Government-led industrial relations working groups of employers and unions discussed the key reform areas ahead of the laws being drafted.

Mr Porter wants consultations to continue once the bill is introduced to parliament.

“I will be listening carefully not merely to all the business groups but also the union groups about their views on the final product,” he said.

“It’s quite clear that not everyone is going to love everything in the final product and it has been something of a balancing exercise.”

He said everything in the bill was important because the reforms were based on job creation.

In the working groups, unions proposed allowing resource and construction projects worth more than $5 billion to have one-year extensions provided there was dispute resolution on the sites.

But mining and resource employers wanted greenfields agreements doubled to eight years.

ACTU secretary Sally McManus has raised concerns the legislation could remove workers’ rights and punish supermarket staff, young people and women.

“We fear it will seek to weaken protections, when the experience of the pandemic has shown the importance of having these protections, when we have been reminded that our social contract must be treasured,” she told the National Press Club earlier in the week.