A climate change campaigner has described the UN Climate Change Conference as "probably the most important international meeting ever".
Chris Walker from the Campaign against Climate Change, stated: "It is the last chance to avoid major, long-term climate change."
However, he expressed doubts that an agreement reached in Copenhagen would go far enough, commenting that the timescales under discussion are too long.
More than 100 world leaders, including US president Barack Obama, are attending the summit, which runs until December 18th.
Delegates are hoping to agree targets setting out a substantial reduction in greenhouse gas levels created by developed nations, while raising a significant amount of money to help poorer countries meet their climate change obligations.
Conference president Connie Hedegaard said that the key to reaching an accord lies in finding a way to provide finances to developing countries to help them fight the effects of climate change.
Mr Walker added that the UK should take the lead by introducing short-term, radical policies relating to climate change.
Posted by Lauren Steadman