The ACTU is pushing for changes to fair work laws to include multi-employer or sector bargaining, which would allow multiple workplaces to make an agreement together.

But Opposition Leader Peter Dutton has labelled the proposal as a throwback to the 1970s-era of industrial relations, which he says will cause crippling strikes.

Burke said the government was “open” to looking at the proposal at next week’s jobs and skills summit.

“I do have to say, I am very interested in what the ACTU have put forward,” he told the ABC on Thursday.

“You can’t get wages moving without getting collective bargaining moving.”

Treasurer Jim Chalmers said he wasn’t “naive” about the contentiousness of the issue, but that the current system wasn’t delivering “strong responsible sustainable wages growth”.

“I do share the broad view that one of the reasons why we haven’t seen the wages growth that we want to see in our economy for the best part of a decade is because enterprise bargaining is broken,” he told ABC radio.

When asked about the ACTU backing a call from the Australian Workers’ Union for all skilled migrants coming into the country to be automatically signed up to a union with an “opt out” clause, Burke said he wouldn’t rule anything in or out ahead of the summit.

“We’re leaving it on the table,” he said.

“We have freedom of association principles, they’re not going to change.”

Greens leader Adam Bandt has thrown his support behind the union proposal.

Bandt said he supported the union proposal, but it would require a legislative change to make to take place.

“Any outcomes from it are going to need a change to the law to do things,” he told ABC Radio on Friday.

“Our position is that workers should be able to bargain collectively at whatever level they choose, at the workplace level, at the industry level, across several workplaces, if they so choose.”