Cameron has regularly stressed his green credentials since becoming leader, describing himself as "passionate about our environment." He has argued that "there is a price ... for tackling climate change" but it is a "social responsibility to the next generation". He has stated he is committed to achieving the 2010 emissions limit and has announced he would change the current Climate Change Levy to a carbon tax in order to counter global warming. Cameron proposed a Climate Change Bill which would include committing to binding annual carbon reduction targets. However, a memo that was leaked to the Labour Party suggested the binding targets proposal may be dropped, and these do not form part of the proposed Bill as of November 2006.