Peter Dutton questioned the costings of Labor’s revamped income tax package but indicated the Liberal Party would back the changes.

“Australians are in need of support at the moment,” the opposition leader said on Friday.

“We do believe that there’s a black hole in the government’s costings, and we’re analysing that at the moment and we’ll make our announcement in due course.”

The opposition has spent more than a week accusing the prime minister of breaking a promise by amending the stage three tax cuts.

But Mr Dutton said the Liberal Party “has always been the party of lower taxes, and that’s going to continue”.

The shadow cabinet will meet in Canberra on Monday to formalise its position, with legislation underpinning the changes expected to be introduced to parliament next week.

Treasurer Jim Chalmers urged the coalition to back the new-look tax package.

“We have found a much much better way to deliver a similar amount of tax relief with a bigger emphasis on middle Australia and it’s better for our economy,” Dr Chalmers said.

Independent MP Zali Steggall, who represents the seat of Warringah on Sydney’s northern beaches, noted that some of her wealthier constituents would be worse off under the changes.

“I’m getting lots of great feedback from the community, some people are very upset but some people are understanding the need to provide more assistance to others that are on lower incomes,” she told Sky News.

Ms Steggall said she would wait to see the legislation before making a final decision.

Labor has the numbers to get the changes through the lower house, but if the coalition decides to oppose the package, the government will need to negotiate with the Greens and Senate cross bench.