Leaders from across the UK's religious communities have said there is a "moral imperative" to tackle global warming.
Leaders from the Christian, Jewish, Muslim, Hindu, Sikh, Buddhist, Baha'i, Jain and Zoroastrian faiths called on G20 nations to cut greenhouse gases.
They said climate change posed a "very real threat to the world's poor".
Their joint call at a meeting at Lambeth Palace in London precedes the Copenhagen summit which aims to deliver a new global climate treaty.
In a statement, the religious leaders urged G20 governments to fight for a deal which would quickly end global reliance on fossil fuels.