Question marks are hanging over a plan to cut the migration intake as the shadow treasurer stumbles over the statistics underpinning the coalition's signature policy.
A move to slash migration and ban foreigners from buying existing homes was outlined by Opposition Leader Peter Dutton following the budget last week as a way to free up housing supply.
Delivering a post-budget address on Wednesday, Shadow Treasurer Angus Taylor said the coalition was looking at reducing what's known as net overseas migration by 25 per cent over a three-year term of government.
The numbers were inconsistent with those spelled out by the opposition leader yet Mr Taylor would not be bogged down in the detail, noting that the ultimate point of the exercise was to "free up 100,000 homes for Australians".
He stressed Australia was a "proud migrant nation" but there were not enough homes to support new arrivals.
"This is a mathematical reality," he said.
"We cannot wish our way into more housing."
Treasurer Jim Chalmers said the opposition's migration strategy was a "smoking ruin" following the speech.
"Mr Taylor couldn't explain the migration numbers which were at the very core of Peter Dutton's budget reply," Dr Chalmers told reporters in Launceston.
Both major parties have expressed interest in slowing down migration, which picked up strongly when borders opened after the COVID-19 pandemic, although their approaches differ.
In his National Press Club address, Mr Taylor called for a "back-to-basics" economic strategy, focused on lifting productivity growth and reining in government spending.
The Albanese government had abandoned the "fiscal guardrails" put in place by the coalition government, he said, and promised to restore them if elected.
The opposition has already committed to overturning changes to the definition of a casual employee, which the shadow treasurer says was just the beginning of his plan to kickstart ailing productivity growth.
"Labor has all but given up on productivity reform, with its revised assumption of 1.2 per cent average growth looking heroic against the experience of the last two years," Mr Taylor said.
"This collapse in productivity makes sustainable increases in real wages, which we all want to see, impossible."
The shadow treasurer was also questioned on the opposition's push for nuclear power following new energy costings from CSIRO and the Australian Energy Market Operator.
The report found the cost of building a large-scale nuclear power plant would be at least $8.5 billion.
But Mr Taylor said any projects should not be subsidised and any industry in Australia should stand on its own.
