THE Opposition Leader, Tony Abbott, has again questioned the scientific evidence for climate change, saying he does not accept that carbon dioxide is a proven ''environmental villain'' or that cutting greenhouse gas emissions is the most important environmental challenge.

The Minister for Climate Change, Greg Combet, seized on the comments by Mr Abbott yesterday as ''proof'' the Liberal Party's climate policy is based on ''the extreme view that climate change doesn't exist''.

Under fire ... Tony Abbott. Credit:Craig Abraham

Speaking at a community forum in Perth, Mr Abbott said: ''I don't think we can say that the science is settled here.

''There is no doubt that we should do our best to rest lightly on the planet and there is no doubt that we should do our best to emit as few waste products as possible, but, having said that, whether carbon dioxide is quite the environmental villain that some people make it out to be is not yet proven.