The federal government looks set to clash with unions and Labor over changes to workplace laws it says are needed to save millions of jobs as COVID-19 restrictions hit the economy.
Industrial Relations Minister Christian Porter on Sunday said the $130 billion package to pay employees at risk of unemployment required changes to industrial relations legislation.
His comments followed warnings from Australian Council of Trade Unions boss Sally McManus that the move to alter the Fair Work Act could have unintended consequences.
Labor has also called for the Coalition to use the industrial umpire to make workplace relations changes needed for wage subsidies, but would not say whether it would oppose legislation in parliament.
The disagreement hangs over a parliamentary sitting on Wednesday in which a fraction of MPs are expected to vote on the government's six-month wage subsidy package aiming to keep people in work.
Ms McManus told the ABC on Sunday the government should change the workplace system through awards and enterprise agreements, not the Fair Work Act.
Not all enterprise agreements would require changes for the JobKeeper package to reach workers, she said.
The unions leader urged the government not to "tinker" with workers' rights in the Fair Work Act by rolling out the JobKeeper package.
"We've demonstrated it's not necessary, there's been changes to awards the last couple of weeks covering millions of workers. We're worried if you change the rights of workers unfortunately some employers might abuse that," Ms McManus said.
She believed employers in non-coronavirus affected industries could use law changes to reduce their liabilities by making staff take annual leave.
Ms McManus is recommending Labor and the Greens oppose changes to workplace laws.
Mr Porter said the government would not wait for changes to more than 100 awards and thousands of enterprise agreements before it made wage subsidies available. Federal parliament would pass the industrial relations changes on Wednesday, he said.
Mr Porter said his office and department were drafting changes to industrial relations laws needed for fortnightly $1500 JobKeeper payments to reach workers, flagging the legislation would be "stress tested" on Monday.
Changes to workplace laws would be time-bound, ending with the JobKeeper package in six months, Mr Porter said.
Labor industrial relations spokesman Tony Burke urged the Coalition to avoid taking a "sledgehammer approach" by changing the Fair Work Act, saying it could have "unforeseen, unintended and bad" consequences.
Unions and Labor are also concerned casual workers will miss out on wage subsidies because they haven't had 12 months continuous service.