Environment ministers from the world's largest polluters, including the United States and China, meet Monday in Mexico under a US bid to speed up work towards a key United Nations climate accord. The so-called Major Economies Forum (MEF) aims to help form a new agreement to curb greenhouse gases to replace the Kyoto Protocol when it expires in 2012. The group's third meeting in as many months comes as worldwide climate negotiations are stalling ahead of a major Copenhagen summit in December aimed at producing the new UN accord. Twelve days of international climate change talks ended last week in Germany without progress on the biggest question of how to share the burden of future emissions cuts. Poor nations are seeking deep cuts from rich countries which are historically most to blame for today's problems. They are mostly calling for cuts of around 25-40 percent by 2020 compared with 1990 levels. Some nations, including China, have said 40 percent must be a minimum. Within industrialised nations, the European Union (EU) has offered a cut of at least 20 percent over 1990, but Japan and the United States have so far offered reductions of around eight percent and four percent respectively. The MEF was launched by US President Barack Obama on the back of a similar initiative by his predecessor, George W. Bush. Its members already met in Washington and Paris in April and May. Participants include Australia, Brazil, Britain, Canada, China, the Czech Republic, Denmark, France, Germany, India, Indonesia, Italy, Japan, South Korea, Mexico, Russia, South Africa, Sweden and the United States, as well as the 27-nation European Union. Representatives from the United Arab Emirates, Norway and Spain will take part as observers, Mexican officials said. The talks come as international support is growing for a Mexican proposal to raise billions of dollars to fight climate change through a so-called 'Green Fund.' The plan would oblige all governments to pay in cash based on a formula reflecting the size of each nation's gross domestic product, greenhouse gas emissions and population. 