Premier Lara Giddings will today reveal the details of proposed legislation designed to thwart a Tasmanian Conservation Trust legal challenge to the permits for the failed timber company Gunns project.

If the legislation passes the Parliament, trust director Peter McGlone has vowed to challenge it in the High Court.

"It's a threat to the rightful power of courts to review legislation," Mr McGlone said.

"The potential precedent is just horrifying."

He was confident of securing enough support in the community and legal fraternity to take the case to the High Court.

"There are a lot of people out there that will put their lives on hold and dramatically throw their support behind this fight," Mr McGlone said.

Wilderness Society spokesman Vica Bayley said the move to protect the "dodgy pulp mill" from legal threats would galvanise community opposition.

"New legislation to shore up the expired pulp mill permits compounds the existing assessment and governance failures surrounding the project," Mr Bayley said.

"Protecting what was already a dodgy process from legitimate court rulings sets a dangerous precedent on top of process already acknowledged as a low point in Tasmanian governance."

The Examiner understands KordaMentha, receiver for Gunns assets, including the pulp mill, had pushed the state government to deal with the legal threat to improve the permit's chances of being sold.

A KordaMentha spokesman yesterday said the potential legal threat was "one of many issues surrounding the Gunns assets and sale process".

"It has been debated publicly and all potential buyers know about it," the spokesman said.

"Legislation has always been a possible way to deal with the potential threat.

"The receivers have been briefing the government and the opposition about developments in the receivership for more than a year.

"It was discussed as part of the regular briefings and feedback."