Fears are mounting that the implementation of the EU's flagship climate change package could be delayed beyond the end of the year, after it emerged that member states are at loggerheads over almost every aspect of the legislative programme.

Despite last year agreeing unanimously to targets that would require the EU to cut carbon emissions by 20 per cent and source 20 per cent of energy from renewable sources by 2020, member states are now split on how the costs of meeting the targets will be shared.

Officials are increasingly concerned that with a number of member states arguing that the economic crisis means many of the measures should be watered down, the European Council is unlikely to reach a final agreement on the proposals.

The Council has to agree on the package in the coming weeks if the measures are to be voted into law before the end of the year - a timeline the EU was keen to stick to as it will strengthen the bloc's credibility and negotiating position ahead of next year's UN talks to agree a successor to the Kyoto Agreement.

Central to the disagreements are reforms to the EU emissions trading scheme that would see carbon -intensive industries such as energy, chemicals and steel having to buy an increasing proportion of their carbon credits at auction.

According to a spokeswoman for the European Parliament, coal-reliant countries such as Poland and Slovakia are opposing measures that would see energy firms have to buy 100 per cent of the credits they require at auction from 2013. Meanwhile, Germany has also been pushing for some energy-intensive sectors to be exempted from the auctions amid fears that increased costs will force them to relocate outside the union.

In an attempt to reach a compromise, French president Nicholas Sarkozy, who is heading up the talks in his role as current EU president, has proposed continuing to provide energy-intensive sectors, such as steel, aluminium and cement, with free carbon credits.

But this has prompted fierce opposition from green groups and several member states, including the UK, who have argued it would undermine the credibility of the entire package.

According to sources, Greece is also looking to renegotiate elements of the package covering funding for carbon capture and storage (CCS) technologies over concerns that the country's geological instability means it will not be able to benefit from the approach, while the UK is continuing to attract criticism over its attempts to water down the rules governing renewables targets.

There is also on-going debate about new standards governing carbon emissions from cars, with a spokeswoman for the European Parliament claiming that the proposed legislation put forward by France and Germany is now "completely different" to that approved by the parliament's environment committee.

The talks are now so locked that Italy has proposed that with Europe on course for recession the entire package should be renegotiated.

That proposal has been rejected by the UK, among others, who are still confident a deal can be brokered.

"Our position remains that this is a major priority and it will prove more cost effective to act now rather than in the future," said a spokeswoman for the Department of Energy and Climate Change.

However, Brussels insiders are less optimistic about the prospects for the package.

"There are splits over a number of topics and some on the council now want to renegotiate the whole package," she said. "The French presidency wants it wrapped up by the end of the year, but there is a lot of horse trading going on and that could take time."

The deadlock yesterday prompted an impassioned defence of the climate change plan from European Commission chief José Manuel Barroso, who warned that the EU's standing around the world was on the line.

"The targets have been agreed and we have presented them all over the world, " he said. "There will be a real problem of credibility for Europe... Saving the planet is not an after-dinner drink, a digestif that you take or leave. Climate change does not disappear because of the financial crisis."