The Community and Public Sector Union (CPSU) is criticizing the federal government for "short-sighted budget decisions" after the Australian Bureau of Statistics (ABS) told workers it would shed up to 150 jobs.

"We are seriously concerned that the ABS is continually being forced to make decisions solely based on its meagre budget," said CPSU deputy national secretary Melissa Donnelly.  "The Bureau needs adequate funding to provide robust, accurate data, and that's clearly not currently the case."

ABS chief operating officer Jonathan Palmer said the redundancies were needed to "transform the workforce for the future and manage effectively within our budget".  He sent an email to staff seeking volunteers, noting that offers would be extended to those expressing interest by 9 February.

The ABS is under fire for the 2016 census and the 40-hour website outage that prevented thousands of Australians from completing forms in August.  But the federal opposition says the government is wrong to cut the ABC budget.

"Now the very public servants who have worked so hard to rescue the census disaster are being forced to pay the price for the Turnbull Government's mismanagement with their jobs," said Shadow Assistant Treasurer Andrew Leigh.  "This government's ideological obsession with downsizing the public service has blinded it to the important work that ABS staff do to inform public policy and help allocate government resources to where they are needed most," he added.