The Greens are “pound for pound” Australia’s biggest climate wreckers, Australian Workers’ Union boss Dan Walton has said as he defended gas as the primary bridge to a renewables future and vital to keeping local manufacturing alive.

A day after the Greens party room said it would not back Labor’s planned heavy emissions reduction policy – the so-called safeguard mechanism – unless it included an overt ban on new fossil fuel projects, Mr Walton said the scheme was vital to guiding the country to a sustainable pathway for net zero by 2050.