Tasmania's Lower House is set to pass legislation aimed at ending decades of conflict in the state's forest.

Tasmanian Greens leader Nick McKim says his party will approve the bill, which was heavily amended by the Upper House.

Mr McKim told Parliament the changes mean that there is a chance that new forest reserves will not be created but peace deal signatories had asked the Lower House to pass the bill unamended.

"But the bill nevertheless provides...the chance of an absolutely stunning and historic conservation gain for Tasmania," he said.

Greens forestry spokesman Kim Booth has indicated he will cross the floor but the Government will still have the numbers to make the peace deal law.

Earlier this month, the Upper House supported the legislation but made significant amendments.

The signatories announced this morning that they would back those amendments.

The Premier, Lara Giddings, told parliament the forest industry will be better off with the peace deal.

"Today is indeed a historic day. Today is indeed an important day for the forestry industry and today the Liberal Party show their true colours - they don't care."

"We will be able to build a new future for Tasmania, a new future for forestry industry."

The Opposition's Peter Gutwein says in Government, says the passing of the bill will not end the long conflict.

In government, the Liberals will undo any new reserves.

"We will do everything that we possibly can to unlock every single stick," he said.

Australian Greens Leader Christine Milne says whether or not the deal's enabling legislation passes State Parliament, it will not resolve conflicts over forest protection.

Senator Milne says in her opinion the peace deal is worthless.

"What is now before the parliament is not the Tasmanian Forest Agreement, it is a remnant, it is the burnt ashes of what went up to the Legislative Council and they're now into a salvage operation," she said.

The Lower House is expected to sit late this evening before finalising debate.

Sweeteners

The State Government has offered a range of sweeteners to help get the deal across the line.

The Wilderness Society's Vica Bayley says the Upper House amendments shook the confidence of environmental signatories.

"The amendments don't reflect the agreement, but what we have done is to try to restore confidence by alternative measures," he said.

"[They are] things such as transferring the management of future reserves from Forestry Tasmania over to Parks and Wildlife.

"Things like a very strong commitment from Forestry Tasmania not to log the future reserves.

"It is utterly clear that this is the only pathway forward."

The Forestry Industries Association's Terry Edwards says the amended legislation is closer to what loggers originally wanted.

But he says the environmental NGO signatories are still getting a very good deal.

"There's no doubt that the amendments made in the Legislative Council probably went further towards what we had originally bargained for," he said.

"But that said, if the bill couldn't deliver on the ENGOs' outcomes, then it wasn't going to deliver on the outcomes of the agreement as a whole."

Mr Edwards says it is an historic outcome, but there is still more negotiation ahead.

"Vica talks about the opportunities presented being too important to lose and I certainly agree with that."

"But it's those opportunities that we, as the signatories, and the two governments need now to seize to see whether or not we can actually do what we've promised to do."

Mr Edwards says the Legislative Council has served voters well with its amendments to the deal.

"To me they did a thorough job, to the best of their ability, inside the knowledge base they had," he said.

"They applied a very strict public interest test over an agreement that was negotiated by people that do not have a public interest test.

"It's our job now to work out how we implement that."

Yesterday, environmental fringe groups labelled the bill 'mutant' legislation and warned they will not stop protesting if it becomes law.