Proposals to tax the flatulence of cows and other livestock have been denounced by farming groups in the Irish Republic and Denmark.

A cow tax of €13 per animal has been mooted in Ireland, while Denmark is discussing a levy as high as €80 per cow to offset the potential penalties each country faces from European Union legislation aimed at combating global warming.

Now, a proposal to force rich people everywhere to stick to personal emissions targets offers hope for a fairer climate deal.

"The idea of introducing individual emission targets is a good one," says Saleemul Huq, a developing nation policy expert at the International Institute for the Environment and Development in the UK, adding that the responsibilities of rich people and needs of poor people in all countries need to be considered. However, he is not sure how practical it would be to implement the proposal.