By Tess Ikonomou and Kat Wong in Canberra

First Nations elders are vowing to challenge plans to build nuclear power reactors, warning the opposition’s proposed blueprint will be a “death sentence” for their connection to country.

The warning comes as an Australia Institute survey revealed two in three Australians are not prepared to pay any extra to have nuclear power in their energy mix.

The opposition has pledged to build seven nuclear plants at the sites of coal-fired power stations if it wins the next federal election.

No costings have been provided, and experts have cast doubt on the timeline and proposed sites, but the coalition has promised to provide more detail before voters go to the polls.

One of the sites earmarked for a nuclear plant, Tarong in Queensland, is located on indigenous elder Aunty Jannine Smith’s country.

“Over my dead body. I will be in a tent outside Tarong gates,” she told AAP.

“It’s a death sentence to that land.

“It’s not happening. I can guarantee you now it will not happen at Tarong.”

Ms Smith said building a nuclear plant on that land would be “severing the connection to that sacred site of ours”.

“We are the custodians of the land, the land is our mother and we don’t own our mother, we care for her,” she said.

Queensland Conservation Council’s Paul Spearim said “white Australia has a short-sighted approach to country”.

He pointed to Maralinga and Emu Field in South Australia where the British held nuclear tests.

More than 1000 indigenous people were exposed to radiation from the tests.

“You have forced poison on to the lands of traditional owners, and now Peter Dutton is proposing to create poisons that would last (hundreds of thousands) of years,” Mr Spearim said.

“We have learnt that white Australia cannot be trusted with nuclear power, and you continue to act without care for our sacred country.”

Other sites put forward for nuclear plants include Loy Yang Power Station in Victoria, Callide in Queensland, Mount Piper at Lithgow in central west NSW and Liddell in NSW’s Hunter region.

Small, modular reactors would be built at Northern Power Station in Port Augusta and at Muja Power Station, southeast of Perth.

The latest edition of the benchmark GenCost report, released by the CSIRO and Australian Energy Market Operator in May, found the cost of building a large-scale nuclear power plant would be at least $8.5 billion.

And a survey from the Australia Institute showed 65 per cent of Australians were not prepared to pay any more to have nuclear power in the nation’s energy mix, regardless of their voting intentions.

“The numbers are clear: residents across the country, regardless of who they vote for, don’t support a nuclear future that requires them to pay more for electricity than they already do,” Australia Institute executive director Richard Denniss said.

Doubt has also been cast over the plan’s proposed deadline.

Cabinet minister Bill Shorten noted the two most recently built nuclear power plants, in the US and UK, have both suffered significant cost blowouts and were years overdue.

Prime Minister Anthony Albanese said the coalition’s proposal did not make sense as Australia had some of the best renewables resources in the world.

“The idea that we would go down this road that’s too expensive, takes too long and has no detail attached is just a nuclear fantasy,” he told ABC radio on Friday.

But Mr Dutton defended his plan and said Australians would be “pleasantly surprised” when the costings are eventually revealed.

“It’s a lot of money, there’s no question about that, but this is an investment,” he told Today.

State premiers have presented another hurdle, vowing to block the project in their jurisdictions, but Mr Dutton was unphased.

“We’ll work with them well in government, but in the end, the Commonwealth legislation overrides the state legislation, so it’s a moot point,” he said.