Yesterday, the Education Department and Australian Education Union accused each other of stalling a case that is now before the Tasmanian Industrial Commission.

The government yesterday indicated that it no longer needed approval in the commission to change teacher holidays.

AEU state president Terry Polglase said the government was trying to short circuit due judicial process.

``This is a heavy-handed approach from the government seeking to force through change by ministerial edict and is an affront to the industrial relations system in Tasmania and the principle of the separation of powers,'' Mr Polglase said.

``The Department of Education had argued fervently for the issue to be sent to the commission for settlement citing lack of time for negotiations. They've now done a 180-degree turn and claim the Minister has the power to legislate the changes outside of the commission (and therefore) circumventing due process or proper negotiation.''

He warned that it set a dangerous precedence for all public sector workers - and said the union was seeking legal advice ahead of returning to the commission on Thursday.

However, department deputy secretary Andrew Finch said it was trying to provide certainty to the community.

``We have been frustrated by a number of stalling tactics utilised by the AEU,'' Mr Finch said.

``We are (now) proposing that the timing of the taking of leave for teachers be subject to a ministerial direction, which is a provision of the Tasmanian State Service Act to specify certain working arrangements for employees. This aims to ensure that teacher leave periods align with term breaks for students and schools.''

Mr Finch said the change would not result in any reduction in teachers' holidays.

Opposition education spokesman Michael Ferguson said parents, students and school administrators had already begun to make plans based on the proposed school terms dates.