Prime Minister Anthony Albanese has labelled changes to Australia's workplace laws as an opportunity to rebuild an outdated system.
With debate expected to continue late into the night on Wednesday on industrial relations reforms that would allow for multi-employer bargaining, Mr Albanese said the changes would ensure better pay for workers.
"This bill represents an opportunity for Australia to move beyond a system that's not serving the best interests of anyone and embrace one that serves the common interest," he told parliament on Wednesday.
"What we are seeking is consensus on a common goal: an economy with strong growth, high productivity and fair wages."
Opposition and crossbench MPs have raised concern the changes could greatly affect small businesses, while also accusing the government of stifling debate on the issue.
Labor is trying to race the measures through parliament by the end of year.
A vote is expected on the bill on Thursday before moving to the Senate, where there will be just two sitting weeks left this year before parliament rises.
Despite opposition to the bill, Mr Albanese said the legislation struck the right tone among stakeholders.
"I understand that there are both business representatives and union representatives who feel that this legislation isn't exactly what they want," he said.
"To me, that says we've got the balance right."
Mr Albanese said the changes to employer bargaining were essential, because the system as it stood was not working.
"Enterprise agreement take up is at a 30-year low. It's a one size fits all system that is no longer fit for purpose," he said.
However, independent MP Dai Le said the proposed changes would be a burden for small businesses.
"The bill itself has more layers than an onion, and as you try to peel back you can't help but cry at the layers on top of more regulatory requirement for employers, especially those smaller businesses who can't afford lawyers," she told parliament on Wednesday.
"Why is the government rushing into this with Christmas around the corner, on such important legislation that will have unintended consequences."
Liberal MP Bridget Archer said the bill fell short in multiple aspects, with small businesses not given enough time to understand the full impacts of the new measures.
"After a tumultuous few years emerging from the pandemic, and at a time of growing inflation, businesses struggling with staff shortages and rapidly increasing power costs, I can't understand why the government want to thrust these workplace changes upon the hard-working small business owners," she said.
"This bill creates drastic changes to our industrial relations system and the time needs to be taken to carefully examine what the government is proposing."
Several MPs have backed calls for the bill to be split, to ensure that non-contentious elements of the legislation like pay increases for workers could be passed quickly.
Greens leader Adam Bandt said the minor party would support the bill in the lower house, before considering if further changes needed to be made once debate reaches the Senate.
Labor will need the Greens plus one crossbench senator to pass the bill in the upper house.
Mr Bandt said he was supportive of many elements of the bill, but wanted to ensure employees would not be left worse off.
"We don't want loopholes in this bill that might allow people to go backwards, and I think that's the government's intention as well," Mr Bandt told reporters in Canberra on Wednesday
Liberal deputy leader Sussan Ley said the proposed amendments would not be able to save the bill.
"You don't make a bad bill better by picking bits out of it or splitting it, it is a problem and it is going to add to the supply chain crunch I'm seeing around the country," she told reporters.