Protesters have started gathering outside Victoria's Parliament to voice their opposition to the upcoming closure of the Gippsland-based Heyfield timber mill.
The mills' owner Australian Sustainable Hardwood (ASH) last week rejected an offer from the Victorian government to supply timber opting instead to close the operation in 2018.
Dozens of log trucks will park in the city as part of Tuesday's protest, which will get into full swing at 11am with a march from Trades Hall to Parliament.
Premier Daniel Andrews offered to buy the mill if the owners didn't accept the government's timber supply offer of 80,000 cubic metres in the first year of a new deal and 60,000 cubic metres in the two years after that.
ASH says it needs at least 130,000 cubic metres a year to keep the mill operating with 250 staff.
Opposition leader Matthew Guy said it is a "ridiculous policy" by the government to buy the mill and reasserted the wood supply for the mill was available.
"This is a cry for help from workers whose families are going to be without a primary income because the government won't do enough to save their jobs," Mr Guy told reporters on Tuesday.
He said the protesting workers were "the heart and soul of Gippsland."
Government-owned VicForests harvests the timber for ASH and said the supply offer was "at a level we believe can be sustainably produced" while also considering existing contracts with other customers.
"We share the concerns that have been raised over potential impact on jobs and the town of Heyfield as a result of the reduction in timber available to the mill," VicForests acting chief executive Nathan Trushell said on Friday.
The CFMEU doesn't accept what VicForests is saying about the availability of timber, Victorian forestry division secretary Frank Vari says.
"Members have made it clear their jobs are not for sale. We don't care who owns the mill - it's the jobs that matter," he said in a statement.
The Tasmanian government says it would welcome "with open arms" Heyfield and any forestry businesses considering moving their operations.