Bill Shorten's union says the Adani coal mine should go ahead if it stacks up financially, as the Labor leader says he's increasingly sceptical of the project.
The Australian Workers Union - which Mr Shorten once led - on Tuesday said coal mining was a major part of its workers' supply chain.
"We are a heavy intensive manufacturing union, for steel and aluminium, we rely on coal as base load power generation to keep most of these going," union secretary Daniel Walton told Sky News.
"Australia needs a coal industry going forward and if this project, like so many others, stacks up viably, financially and everything else, then it should go ahead."
Mr Walton said if the United States' proposed steel tariffs go ahead, Adani's projects could be a market for Australia's surplus steel.
Mr Shorten has faced pressure from conservation groups and voters in a Melbourne by-election to back away from the mine, the merits of which he is "increasingly sceptical".
"Not one of our big banks wants to invest in this project ... no super fund in Australia is investing in this project. Adani has missed a whole lot of deadlines," Mr Shorten told reporters on Tuesday.
"We believe the projects have to stack up commercially and environmentally."
