BANGKOK, (Reuters) – Poor nations demanding a slice  of rich countries’ GDP to fight climate change is a waste of  time, and the fairest method would be a global fund to which  all major emitting nations would contribute, Mexico said yesterday.  

Mexico has proposed the creation of a green fund based on  nations’ historical and current greenhouse gas emissions, GDP  and population as a way to unlock potentially hundreds of  billions of dollars in annual spending. 

Developing countries could receive financing to help cut  emissions through clean-energy investment in programmes that  could be measured and verified.  

Climate finance is a make-or-break issue in talks to try to  agree on a broader framework by a U.N. deadline in December,  when environment ministers from around the world meet in  Copenhagen. “Realistically, you can either sit and ask for ‘X percent’  GDP of developed countries and get nothing or you can ask for a  donor-driven scheme,” Fernando Tudela, the head of Mexico’s  delegation at U.N. climate talks in Bangkok, told Reuters in an  interview.  

The fund is one of several proposals delegates from about  180 nations are discussing in U.N. climate talks in Bangkok  aimed at narrowing differences over how to share the  responsibility in a global fight against climate change.  

The G77 bloc of developing countries wants rich nations to  cut emissions between 42-45 percent below 1990 levels by 2020  as part of a broader climate pact to replace the Kyoto Protocol  and to contribute up to 1.5 percent of their GDP to climate  funds.