Glencore copper processing workers have been guaranteed their jobs in north Queensland for at least three years under a deal struck with the state government.
The mining giant has been reviewing the viability of its copper smelter in Mount Isa and Townsville refinery amid global competition and high fixed costs in Australia.
The Queensland government has stepped in to help foot the cost of rebricking the smelter, which will help guarantee the stability of 1000 jobs until after 2022.
Premier Annastacia Palaszczuk on Wednesday refused to divulge how much money the government would provide but it's understood to be between $30 million and 40 million.
"That's commercial in confidence but funded by consolidated revenue," she said.
The premier made the announcement in Townsville, the location of three of Labor's most marginal seats, ahead of the state election on October 31.
"This is an investment by my government to ensure we keep people in long-term, secure jobs," Ms Palaszczuk said.
"We know how important these jobs are. They're important to the Townsville economy. They're important to the Mount Isa economy."
Glencore chief operating officer of copper assets Matt O'Neill said the state government support with capital expenditure would "level the playing field" for his company internationally.
He said it would also allow Glencore to invest more than $500 million across its Queensland operations.
"The continued focus from the state government on jobs and also keeping advanced manufacturing here in the north is really pleasing and looks after the jobs that we currently have today," Mr O'Neill said.
"Particularly, in this time when we're all looking to try to recover from the impact the virus has had on us, not just on our business but also on our personal lives."
The government says the funding for rebricking the smelter will protect 220 jobs at the Townsville refinery, 350 at the Mount Isa smelter and 520 jobs at Incitec Pivot.
About 230,000 tonnes of copper are shipped from Townsville annually.
The premier also unveiled $30 million in funding for the Big Rocks Weir north of Charters Towers.
Another $10 million has been promised for Drive It, a motorsports and driver training precinct in Townsville, and $19 million for the extension of Riverway Drive.
Labor MP Aaron Harper, who attended the announcement, holds the local seat of Thuringowa by 4.1 per cent and outgoing Disability Services Minister Coralee O'Rourke holds nearby Mundingburra by just 1.1.
Scott Stewart, who holds the most marginal seat in the state at nearby Townsville by 0.4 per cent, also attended Wednesday's announcement.
Queenslanders goes to the polls on October 31.