Christian Aid supporters from all over the UK, including eight members of the clergy from the Highlands to Cornwall, massed in London on Wednesday to demand an escalation of the fight against climate change.

Together with staff from the development agency's London headquarters, they formed a People Map of the United Kingdom to demonstrate that nationwide support exists for a tough new international climate deal.

The rally marked the launch of Christian Aid's Countdown to Copenhagen campaign which says that the new deal that will be discussed when the international community meets in Denmark next year must prevent catastrophic climate change while ensuring the world's poorest people still have the right to development.

Christian Aid warned that poorer countries that have done the least to cause global warming are already bearing the brunt of its impact through drought, flooding and a higher incidence of disease caused by extreme weather conditions.

People Map participant the Rev Zam Walker from Hove said: "The impact of climate change on vulnerable communities in many developing countries is already significant and indeed accelerating. It is up to us to take action. I felt I had to join Christian Aid in drawing attention to the problem, and pressing for a fair climate change deal in Copenhagen in 2009."

Christian Aid said a deal had to be reached at Copenhagen as it is anticipated that governments will then need two years to ratify what is agreed there, and it is essential the new agreement is in place by the time the first commitment period of the Kyoto Protocol, which at present limits emissions for signatory states, ends in 2012.

Most scientists now agree that if global temperature rises are to be kept within 2?C of pre industrial levels - beyond which climate catastrophe is predicted - industrialised countries must commit to carbon cuts of at least 80 per cent by 2050, said Christian Aid.

The aid agency added that target must be included in the Copenhagen deal, as well as a commitment from rich countries to help pay for poor countries to develop cleanly, and adapt to the impacts of climate change.

As European Union leaders met in Brussels today to discuss Europe wide action on climate change, Christian Aid director Dr Daleep Mukarji told the rally: "We are here today to tell the UK government, and members of the European Parliament, that in the name of justice we want carbon cuts of at least 80 per cent by 2050, and help for poorer countries that will compensate them for the damage already caused.

"Carbon emissions in the UK per capita are more than 30 times higher than in Bangladesh or Senegal. Yet those countries are paying the price for the industrialised world's pollution through severe flooding and drought respectively.

"There are many other examples from countries in the developing world of the suffering caused by global warming. If our leaders do not take better and urgent action on climate change, their plight will steadily worsen."

All participants signed a pledge reading: "I believe in a world free from the poverty and injustice caused by climate change." They also held aloft banners identifying the place they represented, and a message saying they supported Christian Aid's demands.

Participants also heard from Marcos Nordgren, representing a Christian Aid partner from Bolivia, CIPCA (Centre for Research and Training of Peasants) about the impact of climate change on his country. Bolivia's per capita annual carbon emissions amount to Bolivia is 0.8 tonnes. The UK figure is more than 10 times higher.

After the event, a delegation of Christian Aid supporters met Joan Ruddock, Parliamentary Under Secretary of State in the Department of Energy and Climate Change.

To join the Christian Aid Countdown to Copenhagen campaign visit www.christianaid.org.uk/copenhagen