Alex Salmond has escalated the row over David Cameron's plans to roll back green levies by accusing him of planning to take actions "which in planetary terms are suicidal."

The Scottish first minister said Cameron was more concerned about winning the next election than addressing the very real dangers of climate change.

Salmond's intervention came as Downing Street said it does not recognise reports that the prime minister wants to "get rid of all the green crap" from energy bills to bring down costs. According to the Sun, the prime minister was referring to the green levies, which fund renewables and reduced bills for poorer people and which make up £112 of the average bill.

He has already promised to roll back green costs, which currently make up £112 of the average bill, over concerns about the record energy prices.

Salmond, who was speaking at the first global conference on natural capital valuation in Edinburgh, said: "He's gone a mile of a difference backwards since he was hugging polar bears. Is this the same prime minister who said he was going to lead the greenest government in history?

"It is quite legitimate to take some of the energy efficiency levies off electricity bills and put them onto the public purse as that is a far better way to organise these schemes yourself rather than through power companies.

"But the idea that you should abandon, for example, the move towards renewable and green energy is absolute madness.

"In a word, what is driving it is 2015. I think David Cameron should be thinking of 2020 and 2030 and not just about his own election prospects."

Salmond claimed that Scotland had built five to six times as much renewable energy capacity as the UK as a whole, on a proportional basis.

He also said that the UK was facing a shortage of generating power over peak demand in two years time and that the lights would already be going out south of the border if it were not for Scottish renewables. Abandoning green levies would put energy security even further at risk.

Referring to the slow progress of global climate change talks in Warsaw, Salmond said: "The environmental global challenge we face is not less than it was in 2010 when Cameron came to office but overwhelmingly more and the action being taken to deal with it is falling far, far short of what is required.

"Cameron's actions have got to be self-defeating as people will see through them. It is irresponsible in terms of our obligations to the planet.

"We have now achieved a 25% reduction in our CO2 from the 1990 base line. I don't see why that cannot be the aim of the government south of the border. It does not require us to make huge sacrifices, it just takes steady application of purpose.

"I would argue, like DECC [The Department of Energy & Climate Change] would argue, onshore wind energy is likely to be cheaper than fossil fuel alternatives by 2020, so what would be the reason for turning away from green issues at the present moment apart from Cameron having been wrong footed by Ed Miliband over electricity bills. He should do something sensible rather than taking actions which in planetary terms are suicidal."

Salmond's intervention came as he announced the launch of the Scottish Forum on Natural Capital, a new project aimed at bringing together public, private and voluntary sector organisations to protect and rebuild Scotland's natural capital.

The creation of the forum, which includes the Scottish Wildlife Trust, the University of Edinburgh, the Institute of Chartered Accountants in Scotland (ICAS), and the Institute of Directors, Scotland, follows academic research that shows nature is worth between £21.5bn to £23bn per year to the country's economy.

Salmond said: "An early focus for the Scottish Forum will be on peatlands, which is especially fitting since they form a substantial part of the Scottish landscape and are widely recognised as important in climate change mitigation, biodiversity and water quality. The Scottish Government has long acknowledged the benefits of peatland restoration and is making every effort to conserve this vital and valuable resource."

Simon Milne, chief executive of the Scottish Wildlife Trust said he hopes the forum will help businesses to understand their environmental impacts and to incorporate them onto their balance sheets.

He said: "We hope that the Scottish Forum will provide a blueprint to other countries of how they can encourage collaboration to find new ways to protect and enhance the natural environment, to the benefit of their people and their economies.

"There is no reason why England and Wales should not be taking this just as seriously, as every country has as much a financial stake in their natural assets as Scotland has."