The fund will be used to promote energy efficiency, "clean coal" and carbon capture in China, reports said.
"We now enter this new era of environmental cooperation," Brown was quoted as saying after a presentation on the proposed Dongtan eco-city project near Shanghai, which British officials said will inform the construction of the Thames Gateway project in London.
UK officials were also reported as saying that China was becoming the world’s leading emitter of greenhouse gases, but that it may suffer the worst from the harmful effects of global warming.
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