The bill is yet to be debated for a third time in the lower house after being dropped from the schedule twice.

“There is already a large backlog of bills in the Senate so once this bill is introduced, unless the government chooses to prioritise it over others, it’s looking increasingly unlikely it will be passed before the end of the calendar year,” Burgess said.

“The problem the government has is that the Senate crossbench does not support the taxation of unrealised capital gains, and without reverting to actual taxable earnings, which Treasury has so far ruled out, it is very difficult to avoid taxing unrealised capital gains.”

Based on discussions the association has already had with the crossbench, Burgess said he agrees with the shadow treasurer Angus Taylor who said there isn't a clear pathway to pass the bill.

Furthermore, he said that given recent discussions about changes to negative gearing, it is more important than ever the sector pushes back against the design of the $3 million super tax.

He said the SMSFA has previously stated taxing unrealised capital gains sets a dangerous precedent for future tax reform.

“It is not difficult to see how this approach could be applied to claw back perceived inequities in other areas of the tax system, including negative gearing. It could be one way the government tempers the tax benefits without amending the rules that underpin negative gearing,” he said.

On Monday, Taylor and shadow finance minister Jane Hume urged the government to scrap its plans to tax unrealised gains in superannuation.

In a statement sent to SMSF Adviser, Taylor said: “Labor’s changes to super are an unindexed, undemocratic wealth tax”.

“There is no pathway to pass this bill, yet it is propping up a budget where Labor’s decisions are costing $4 for every $1 of revenue,” the shadow treasurer said.

“Treasury modelling released under FOI showed that even a 20-year-old earning an average wage today will be captured by this wealth tax because of Labor’s refusal to index the measure.

“Under Labor’s plan, 2 million Australians under 25 will see taxes double on their retirement savings.”