How can world leaders at the Rio+20 Earth Summit next week show that they are serious about sustainable development and environmental protection? The answer is simple: end fossil fuel subsidies.

Every year, governments around the world give nearly $1 trillion dollars of public money to the fossil fuel industry. Three years ago, the G20 committed to phase-out these handouts to coal, oil and gas companies, but they haven't taken any action since.

Now is the perfect time. This June 18, finance ministers and heads of state from G20 countries will come together in Los Cabos, Mexico. Three days later, more than 100 presidents and prime ministers will join over 50,000 people at the Rio+20 Earth Summit, the largest environmental conference in world history. Both meetings offer a clear opportunity for world leaders to step up to the plate and stop these outrageous handouts.

After all, how can you have a serious discussion about funding sustainable development without taking on the hundreds of billions of dollars handed over to the fossil fuel sector each year? A mere fraction of these subsidies could jumpstart thousands of clean energy projects around the world. Large scale transfers of money from dirty to clean investments could catalyze the type of worldwide energy transformation that is desperately needed.

And pony's too.