The Chinese may be renowned for their negotiation skills. But this year's climate summit in Copenhagen hasn't proved very productive. Key states have reached what they call a "meaningful agreement," but many have said the progress made is simply not good enough.

It's widely thought the US and China hold the key to striking a binding agreement in the future. Yet they also pose two major obstacles. One is the Washington's refusal to propose deeper cuts in greenhouse gas emissions. And second is China's refusal to any kind of international monitoring of its emission levels.