Union heavyweight Paul Howes says the Australian Workers' Union will continue to run advertisements promoting mining in Tasmania's Tarkine region, despite protests by lobby group GetUp.
In a statement the AWU said GetUp had written to Howes demanding the union withdraw "misleading" pro-mining advertisements.
But Howes said the AWU would continue to run the ads in an effort to promote expanding mining development in the Tarkine.
GetUp is currently leading a campaign to protect the Tarkine wilderness from mining projects it claims will "destroy" the region.
The AWU says mining needs to expand in the Tarkine to give a boost to Tasmania's ailing local economy.
It says the region is big enough to balance competing land interests, and has always supported a broad range of industries.
"I can assure the anti-mining lobby groups that our members will not be silenced," Howes said.
"They will continue to fight for their jobs, their industry and their future."