Finance Minister Mathias Cormann has warned public servants to stick to the rules if planning to walk off the job for Friday's climate strikes.
Senator Cormann also told students to go to school instead of joining the rallies around the nation.
During Senate question time on Thursday, Greens leader Richard Di Natale asked Senator Cormann - who represents the Minister for the Public Service in the Senate - whether Commonwealth bureaucrats would be punished if they attended the strikes
"Minister, will you as the minister responsible for the public service guarantee that there will be no retribution or punishment against any Commonwealth public servant who leaves work to attend the strikes?" Senator Di Natale asked.
Senator Cormann said bureaucrats "across the great world class Australian public service" knew what their "duties and responsibilities" were.
"I would encourage all of our outstanding public servants to conduct themselves appropriately consistent with the rules," he said.
The minister's office has been approached to clarify exactly what those rules are.
Senator Cormann also had some advice for students planning to ditch school to attend the protests.
"Students should go to school ... that is what will prepare them to be the best possible contributors to their communities and our nation into the future," Senator Cormann said.
Meanwhile, territory public servants have been given the blessing of the ACT government to attend the protests.
Employers including the Canberra Innovation Network, Blueblood Solutions, Community Shapers, Capital Brewing Co and the Australia Institute are among those supporting the strike and allowing employees to march, with many offering extended lunch breaks or even the whole day off to mark the day.
The ACT education directorate said students striking with their parents' permission wouldn't be penalised, after the government again supported the strike as important real-world learning.