“Everything we do here in the Senate in terms of legislation of economic bills should be viewed in the prism of trying to tackle the moral challenges of our time such as inequality,” Mr Whish-Wilson said in the Senate yesterday.

“We do have legislation here today that goes some way to raising revenue from the rich. It’s a shame it didn’t go further. It’s a missed opportunity.”

Mr Greens also raised concerns about how the superannuation changes will affect housing affordability for aspiring first home owners.

Without a review into the tax advantages for investors in real estate, he said “more capital will be diverted into existing housing stock, making it even harder for younger Australians to buy their first home and further entrenching wealth inequality between generations”.

Mr Whish-Wilson earlier told SMSF Adviser that the Greens would prefer to see the tax rate for concessional contributions made progressive, with rates increments aligned with increments in the marginal income tax rate, but at a discounted level.

“The current system provides overly generous concession for high-income earners to contribute to their super fund while penalising the lowest-income earners for their contributions. This makes no sense,” he said.

Mr Whish-Wilson said the Greens did not believe the bills would “fail to provide for the accumulation gap that women experience when they go on maternity leave”.