Photo: Chris Brown. Cardiff Friends of the Earth.
Several members of Cardiff Friends of the Earth were at the protest. One of the group members, Chris Brown, said “We want world leaders to reach a fair, ambitious and binding international agreement. They should cut their emissions of climate change gasses by at least 40 percent by 2020. Doing this will stop global temperatures rising more than 2 degrees C preventing unstoppable climate change.”
“We also want the developed countries to help developing countries to cut their emissions, and for the rich countries not pay poorer countries to make the cuts in their place. Developed countries must not avoid their responsibility for the planet by using carbon offsetting instead of making cuts in their own carbon emissions.” he continued.
Read Adam's report of the march.
In London, police said about 20,000 people had taken part, but they did not contradict claims by the organisers that the actual figure was over 50,000 people.
Similar protests were held in Edinburgh, Belfast, and in other European capitals.
Gordon Brown praised the protesters for "propelling" leaders to reach the "first world climate change agreement". He said it was essential that a deal be reached in Copenhagen and leaders had to be "ambitious".
Mr Brown said he and the "vast majority of people" were convinced by the scientific evidence for man-made global warming.
"There's a flat earth group over the evidence, if I may say so, that exists about climate change, and we've got to show them that the scientific evidence is strong," he said.
"The public need to be angry about the extent to which we have not taken action sufficiently as a world until now, and they've got to then see that the first climate change agreement is not only necessary, it's absolutely essential."
The Copenhagen summit will have representatives from 192 countries who will try to reach a new international agreement on climate change that builds on the Kyoto Agreement.
The European Union has offered to cut its emissions by 20 percent from 1990 levels by 2020, rising to 30 percent if a global agreement is reached.
The US is pledging to cut its emissions in stages, beginning with a 17% cut from 2005 levels by 2020. Washington is currently unable to commit to its pledges for the talks, as a Bill to cap its emissions is currently stuck in the US Senate and will not be passed before the new year.
Australia is in a similar position to the US, after their Senate rejected a Bill to cut emissions.
India and China have both agreed to reduce their "carbon intensity", this is a measure of the amount of carbon dioxide emitted per unit of GDP, meaning that the amount of carbon dioxide they emit will rise more slowly as they develop.
View photos of the protest.
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