The study estimated that energy subsidies, almost all for fossil fuels, totalled about US$300 billion a year or 0.7 percent of world gross domestic product (GDP).

"Cancelling these subsidies might reduce greenhouse gas emissions by as much as 6 percent a year while contributing 0.1 percent to global GDP," it said.

People forced to pay higher prices for energy would likely cut back on use of fossil fuels, the main source of greenhouse gases from human activities.

"Governments should urgently review their energy subsidies and begin phasing out the harmful ones," said Achim Steiner, head of the Nairobi-based UN Environment Programme (UNEP).

"Many fossil fuel subsidies are introduced for political reasons but are simply propping up and perpetuating inefficiencies in the global economy," he said in a statement.

Subsidies were biggest in Russia, with about US$40 billion a year spent mainly on making natural gas cheaper, ahead of Iran with US$37 billion. China, Saudi Arabia, India, Indonesia, Ukraine and Egypt also had big subsidies on fuels.

"Some countries spend more on subsidies than on health and education combined ... they stand in the way of more environmentally friendly technologies," Kaveh Zahedi, climate change coordinator at UNEP, told a news conference.

POOR

The report said liquefied petroleum gas (LPG) subsidies in India, aimed at getting fuel to poor households, totalled US$1.7 billion in the first half of 2008. But the report said: "LPG subsidies are mainly benefiting higher-income households".

Smarter subsidies such as tax breaks, financial incentives or other market mechanisms could generate benefits for the economy and environment if properly targeted, it said. It pointed to subsidies to promote wind energy in Germany and Spain aimed at helping to shift from fossil fuels.

Well-devised subsidies in Chile had spread rural electrification to 90 percent of the population from 50 percent in 12 years, it said.

Governments in Accra are working on the building blocks of a new climate treaty meant to be agreed at the end of 2009 to help slow warming temperatures that may bring more heatwaves, more powerful storms and disruptions to water and food supplies.

UNEP also said Africa was starting to benefit from a UN project to help investments in clean technologies such as wind or geothermal power. Nations such as China, India and Brazil have so far won almost all of the 3,500 projects.

New projects had been registered in recent months in Mozambique, Democratic Republic of the Congo, Madagascar, Mauritius, Mali and Senegal, UNEP spokesman Nick Nuttall said.

And a UNEP study projected that Africa might get 230 such projects by 2012, generating up to US$1 billion in credits. (Additional reporting by Daniel Wallis in Nairobi, editing Mary Gabriel)

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