The European Union says it is beefing up its carbon trading system to make it more expensive for utilities and other businesses to burn fossil fuels.

EU officials on Wednesday voted for a proposal that ended a year of bickering over how to amend what is Europe's prime tool in the fight against climate change.

Under the emission trading system — the world's biggest — companies pay per ton of carbon dioxide they release into the atmosphere, with the pollution certificates traded on the market.

The agreed proposal would postpone the sale of 900 million additional carbon allowances — a move that will tighten supply, driving up prices.

The 28-nation EU introduced the system in 2005 to encourage industries to reduce emissions and invest in greener technologies.