The G20 group of nations has agreed to end fossil fuel subsidies but has not agreed terms for a global climate treaty.

Leaders of G20 nations meeting in Pittsburgh, US, last week, agreed to phase out oil and gas subsidies in the medium term but set no firm timetable on when this will be done.

The move aims to consolidate government energy and climate policy across the world, especially between big developing economies and G20 member states China and India.

Global energy and finance ministers will now have to report back to the next G20 summits in 2010 in Canada and South Korea on possible timetables for withdrawing financial support for fossil fuels.

On the wider issue of climate change, leaders have only agreed on increasing efforts to find a deal in the run up to crucial climate talks in Copenhagen.

Officials meeting in the US last week also stressed that the G20 could not tell countries how to run their economies.

Instead, it will assess national economic policies and rely on a new process of peer review.

Under the plan, the International Monetary Fund (IMF) will forecast the impact of policies and report back to the G20 with suggested changes.