|PIC1|Development groups have expressed their alarm at the breakdown in talks at the UN climate change summit in Copenhagen.

With just two days left to reach a climate deal, negotiators are in deadlock over which countries should cut their carbon emissions and the amount of funds that should be made available to help developing countries mitigate the worst effects of climate change.

As climate secretary Ed Miliband warned that the summit was turning into a “farce”, protests turned ugly outside the conference centre as environmentalists clashed with police in a failed bid to storm the building and a sit-in led to several environment groups being barred from the summit.

Around 120 world leaders are due to join the talks on Thursday, but development groups fear the talks are going to end in failure.

In a letter published in The Guardian, 20 grassroots organisations including Catholic development group Progressio urged world leaders to reach an agreement.

"As representatives of people from the developing world who are most affected by climate change, we are still fighting to ensure our voices are heard in Copenhagen. We are alarmed about the potential failure of the talks,” they said.

"We urgently hope that in the few days left Copenhagen changes the status quo which continues to damage the natural world.”

The aid agencies called on countries in the Global North to “recognise its ecological debt to the world’s impoverished peoples” by rebuilding villages and ecosystems and agreeing “substantial” cuts to greenhouse gas emissions.

“Enough funds should be provided to southern countries to support this socio-environmental restoration: the climate debt to the world's poor must be settled," they said.

"If Copenhagen achieves nothing, the resulting delay in securing a vital climate agreement will be a terrible sentence for all human beings and the planet."

Progressio’s Advocacy Manager Tim Aldred said the next 48 hours would be critical for the world’s poor. Hr said negotiators could not afford to ignore their voices.

“If they do, and if they fail to act, leaders will be doing so in full knowledge of the deplorable consequences that await the one billion worldwide living in extreme poverty. The poor and marginalised will be hit hardest and fastest by the consequences of global warming."

He continued: "So far we have heard many fine words from governments. But unless we see serious movement soon on the critical areas of finance for poor countries and the early cuts in emissions dictated by all scientific opinion, these words will be no more than hollow spin."

There was an eleventh hour reshuffle last night when Danish Prime Minister Lars Loekke Rasmussen assumed control of the talks from Danish cabinet minister Connie Hedegaard ahead of the arrival of 119 world leaders today.

Within hours of the leadership change, Mr Rasmussen came under fire from China's chief negotiator Su Wei for his plans to present a new draft agreement later on Thursday without the prior consultation of all of the negotiating parties, including China, India and Brazil.

“Unfortunately this morning the presidency put forward something from the sky, it’s a parachuted text,” he said. “It’s not simply a matter of procedure. Actually it’s a matter of substance. It’s the respect of the parties from the 192 countries. You cannot just put forward a text from the sky.”

Christian Aid's senior climate advocacy coordinator Nelson Muffah said Denmark had undermined the trust of developing countries by changing the rules again and continuing to "promote their ideas at the expense of encouraging compromise".

He said a deal on climate change should be reached "openly and trasparently" through the existing negotiating groups "rather than behind closed doors between an exclusive group of compliant countries".

Mr Muffah accused Denmark of overstepping its role as facilitator and said the deadlock was symptomatic of the refusal of developed countries "to offer anything like a fair deal for developing countries".

"Instead the rich are trying to bully the poor into taking on more of the burden of solving the climate crisis," he said.

Prime Minister Gordon Brown said last night that world leaders had to "face up to their responsibilities".

He has given his backing to an ambitious deal that would see the UK commit to 42 per cent cuts in carbon emissions by 2020, far higher than the four per cent reduction on 1990 levels offered by the US.

He said: "I do not deny this is difficult and there may be deadlock but I do see a way through."