More than 3,500 community members have signed a petition calling on the NSW Government to oppose the $600 million gas plant.

Tomorrow at 10am the Gas Free Hunter Alliance will join with Northern Beaches groups in a protest outside the office of Rob Stokes, NSW Minister for Planning and Public Spaces, who will personally be responsible for the approval of the gas plant.

The groups plan to meet the Environment Minister Matt Kean in coming weeks.

The alliance includes more than a dozen community groups, opposing the gas plant for reasons including climate change, economic impacts, air and noise pollution.

"There's deep and widespread community opposition to the proposed gas plant," said alliance organiser Mrs Carly Phillips.

"In just a fortnight, more than 3,500 people have signed a petition calling on the NSW Energy and Environment Minister to reject the proposal."

"Communities in the Hunter look to the Minister to fulfil his pledge to make NSW a renewable energy superpower," said Kurri Kurri resident Ms Janet Murray, a member of Coalfields for Climate Action.

"It's time to invest in a diverse regional economy, with decent, long-term jobs."

The Alliance will be door-knocking and convening public meetings to develop an alternative plan for energy and jobs to recommend to Federal Energy Minister Angus Taylor, the gas plant's lead advocate.

"The Minister for Energy and Emissions Reduction, Angus Taylor needs to direct this $600 million of public funding to something more than a project in an outdated industry and that will provide only 10 ongoing jobs. This region needs investment in a strong renewable energy future, not in white elephants designed only to prop up the fossil fuel industry," said Newcastle Climate Change Response convenor Ms Jacquie Svenson.

'The Minister needs to live up to his role."

The petition calling on the NSW Government to oppose the $600 million gas plant can be found here.

Gas Free Hunter Alliance gathered on the site of the proposed gas plant on Wednesday morning.

The Gas Free Hunter Alliance is made up of groups including: Australian Parents for Climate Action; Climate Action Newcastle; Coalfields for Climate Action; Correct Planning and Consultation for Mayfield; Doctors for the Environment Australia; Friends of Tumblebee; Hunter Community Environment Centre; Knitting Nannas Against Gas; Newcastle Climate Change Response; School Strike for Climate.