Trade Minister Don Farrell wouldn't put a specific date on wage increases but said he was confident they would lift in light of the new bargaining powers, which could pass the Senate on Thursday.

"It gives us the opportunity to really, really get wages moving again," he told AAP.

"There's a whole lot of industries out there where people are raring to go."

The opposition is arguing smaller businesses will be forced into agreements and stung with legal costs they can't afford.

Small businesses with fewer than 20 employees will be excluded from single-interest multi-enterprise bargaining.

Businesses with fewer than 50 employees will have extra safeguards if they want to opt out of multi-employer bargaining.

Liberal senator Sarah Henderson said businesses would stop employing more people to remain exempt from multi-employer bargaining.

"Why on earth would you want to grow or say 'I want to put in another 10 people'?" she said.

"This is a job destroyer."

Senator Farrell called the argument a red herring.

"If a business needs extra staff, they're going to be hiring," he said.

"They're out there right now looking for people. The big problem is actually finding staff."

Government Services Minister Bill Shorten said he expected criticism from the business sector of the bill to die down once the legislation passes this week.

"A lot of the scare campaign will evaporate and be seen for just that," he told ABC Radio on Thursday

Prime Minister Anthony Albanese said the current system was not fit for purpose.

"It's not delivering the productivity gains employers need. It's not delivering the wage rises that workers deserve," he told the Australian Chamber of Commerce and Industry.

"We're building a relevant and practical framework that enables employers and employees to negotiate in good faith, to agree on win-win outcomes."

The prime minister refused to bite on warnings from the Reserve Bank governor that Australia could be headed into a wage-price spiral when higher salaries fuel inflation.

"What the Reserve Bank has said is that low wage growth was something that was holding back our economy," he told ABC 7.30.

"If you don't have wages keeping up with the cost of living, then you'll have increased pressure on working families."

Mr Albanese said enterprise bargaining would help boost productivity.

"The way you lift wages without putting pressure on inflation is to boost productivity," he said.

ACTU national secretary Sally McManus said the laws would enable more businesses to recommence bargaining arrangements following the pandemic.

"What this law does is give workers better tools in negotiations for wages," she told ABC TV.

"What happens in terms of the outcomes of that, I guess, in the end is up to both workers and employers."

Australian Associated Press