A senior minister has been accused of "grotesque hypocrisy" ahead of a speech she is to make about the government's plan to tackle climate change.
Energy and Climate Change Secretary Amber Rudd will say measures to curb rising temperatures are about ensuring economic security.
She will also seek to redress the view that green policies are "left-wing".
But Friends of the Earth have accused the Conservatives of "dismantling" 10 years' worth of low-carbon policies.
Ms Rudd is treading a difficult line - Prime Minister David Cameron has promised to lead the world to a climate change deal at a summit in Paris in November.
Subsidies scrapped
But Chancellor George Osborne has announced a slew of policy changes which will increase UK emissions.
In recent weeks he has scrapped subsidies for onshore wind and commercial solar - the two cheapest forms of clean energy.
He has also slashed the energy efficiency budget, ended the tax break for clean cars, abolished rules on zero carbon housing, lowered taxes on polluting firms and introduced a tax on clean energy.
Environmental organisation Friends of the Earth said Mr Cameron was "sticking up two fingers" to nations at the French climate summit.
Ms Rudd has to defend the position of both her bosses - and repel those commentators on the political right who believe climate change is not a problem at all.
"It cannot be left to one part of the political spectrum to dictate the solution - and some of the loudest voices have approached the issue from a left-wing perspective," she will say.
"So I can understand the suspicion of those who see climate action as some sort of cover for anti-growth, anti-capitalist, proto-socialism.
"It was Margaret Thatcher who first put climate change on the international agenda. She (said) 'the danger of global warming is real enough for us to make changes and sacrifices, so that we do not live at the expense of future generations.' I agree."
Ms Rudd insisted that the Conservatives' approach was to devise policies to stimulate low carbon businesses and get them off subsidy as soon as possible to keep bills down.
Industry bodies say the government's recent sudden changes to low-carbon policies have created mass uncertainty for investors.
But Ms Rudd will say: "The Conservatives are committed to action on climate change and we are clear that our long-term economic plan goes hand in hand with a long-term plan for climate action.
"Climate action is about security, plain and simple - economic security.
"The economic impact of unchecked climate change would be profound. Lower growth, higher prices, a lower quality of life. It is the ultimate insurance policy."
'Deeply shocked'
Craig Bennett, head of Friends of the Earth, told BBC News: "This is grotesque hypocrisy from a government that has spent the past few weeks dismantling an architecture of low-carbon policies carefully put together with cross-party agreement over the course of two parliaments.
"They have swept it all away without signalling their intent in their manifesto. They have no mandate for this - it's David Cameron sticking up two fingers to other nations at the climate conference in Paris. Unbelievable."
John Sauven, head of Greenpeace, agreed.
"We are deeply shocked by the vandalism of the government which appears to be driven totally by ideology.