Budget papers in May revealed the Coalition had tasked the Australian Public Service Commission with forming a strategy to grow staff movements between agencies, and the private sector. The government will consider ways to "maximise flexibility" under the plan.

The move coincides with an independent review of the federal bureaucracy, commissioned by Prime Minister Malcolm Turnbull and led by former Telstra chief executive David Thodey, that may lead to its biggest overhaul in more than 40 years.

Community and Public Sector Union national secretary Nadine Flood said the move for a workforce strategy continued a Coalition government attack on agencies and public servants.

“Public sector workers know all too well that when the government talks about maximising ‘flexibility’, that means replacing their permanent, quality jobs with inferior, insecure, lower paid work that costs the government more and delivers less through contractors, consultants and labour hire," she said.

“This strategy appears to be a belated attempt to defend the government’s ideological obsession with selling off critical public services to big business and undermining the kind of public sector capacity that’s needed to run a good government."

The public service commission said it was still planning the new strategy, which would "inform and be informed by" the independent APS review.

"The purpose is to reveal future capability requirements, introduce modern workforce practices and prepare public sector employees for the future," it said.

Employment figures quoted in budget papers showed about 2 per cent of public servants moved agencies in 2017, and nearly three quarters of APS staff had only ever worked in one agency.

"Limited mobility impacts agencies' ability to draw on a broad base of experience when developing programs, designing services for citizens and providing advice to government," the papers said.

Budget papers said the government was taking a "flexible approach" to resourcing involving both permanent public servants, and "selective use" of contractors and consultants.

While the government says its use of consultancies as a percentage of all contracts has been stable, the national auditor found massive growth in work going to consultancy firms since 2012-13.

The findings prompted a new parliamentary inquiry, which has thrown into scrutiny the Coalition's booming contractor spend.

Since the change of government in 2013, annual expenditure on labour contractors for 18 of the largest workplaces has ballooned from $318 million to more than $730 million as the Coalition imposed staffing caps and shed public servants.

A draft paper released on Wednesday, written as part of a separate review by Mr Thodey and Medibank Private chair Elizabeth Alexander, found there was a lack of transparency around spending on contractors in the public service.

It recommended new rules forcing agencies to disclose the government's expenditure on contractors.